diff --git a/src/ASPHERE/compute_erotate_asphere.h b/src/ASPHERE/compute_erotate_asphere.h
index 37429375794c850af8ae85a995b7c720b82ba4fb..e29d15ec244d7b8f09077a03f605f95fc2389729 100644
--- a/src/ASPHERE/compute_erotate_asphere.h
+++ b/src/ASPHERE/compute_erotate_asphere.h
@@ -52,7 +52,7 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Compute erotate/asphere requires atom style ellipsoid or line or tri
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute erotate/asphere requires extended particles
 
diff --git a/src/ASPHERE/compute_temp_asphere.h b/src/ASPHERE/compute_temp_asphere.h
index e6bfc5af24c4d4d71567507870e32ca6784d5058..715150f5e423faa70fbfc8c82cd4284db0eb981d 100755
--- a/src/ASPHERE/compute_temp_asphere.h
+++ b/src/ASPHERE/compute_temp_asphere.h
@@ -60,7 +60,7 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Compute temp/asphere requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute temp/asphere requires extended particles
 
diff --git a/src/ASPHERE/fix_nh_asphere.h b/src/ASPHERE/fix_nh_asphere.h
index 21a9c713dbacc7411c28d8394f19d092d4e7e05d..5c98e412ce8df0e27fb396e840e0cf4de22c597d 100644
--- a/src/ASPHERE/fix_nh_asphere.h
+++ b/src/ASPHERE/fix_nh_asphere.h
@@ -41,7 +41,7 @@ class FixNHAsphere : public FixNH {
 
 E: Compute nvt/nph/npt asphere requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nvt/nph/npt asphere requires extended particles
 
diff --git a/src/ASPHERE/fix_nve_asphere.h b/src/ASPHERE/fix_nve_asphere.h
index 685a2d276346bd260d49d12a7814c0d0f8cb6581..fe6334fd1f1383904e536c5dc3d517df46cb0514 100755
--- a/src/ASPHERE/fix_nve_asphere.h
+++ b/src/ASPHERE/fix_nve_asphere.h
@@ -44,7 +44,7 @@ class FixNVEAsphere : public FixNVE {
 
 E: Compute nve/asphere requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nve/asphere requires extended particles
 
diff --git a/src/ASPHERE/fix_nve_asphere_noforce.h b/src/ASPHERE/fix_nve_asphere_noforce.h
index cc1c497392d552bce05cb929d987289cfd9d38c0..6e0209d722f77fb6f11a28664e1056bf8a0efe99 100755
--- a/src/ASPHERE/fix_nve_asphere_noforce.h
+++ b/src/ASPHERE/fix_nve_asphere_noforce.h
@@ -50,10 +50,10 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Fix nve/asphere/noforce requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nve/asphere/noforce requires extended particles
 
-UNDOCUMENTED
+One of the particles is not an ellipsoid.
 
 */
diff --git a/src/ASPHERE/fix_nve_line.h b/src/ASPHERE/fix_nve_line.h
index 7ad52fdb0b134bd750af2afe08ab9cddcd19f78f..2a2e957be2acb3cfef0639d7c3691c8dee5cf2c5 100644
--- a/src/ASPHERE/fix_nve_line.h
+++ b/src/ASPHERE/fix_nve_line.h
@@ -53,14 +53,14 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Fix nve/line requires atom style line
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nve/line can only be used for 2d simulations
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nve/line requires line particles
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/ASPHERE/fix_nve_tri.cpp b/src/ASPHERE/fix_nve_tri.cpp
index 92fc1320d05291170a29f22648879e7d59a4c2c7..9048f89269eaf32635298fac33514856d92d2785 100644
--- a/src/ASPHERE/fix_nve_tri.cpp
+++ b/src/ASPHERE/fix_nve_tri.cpp
@@ -58,7 +58,7 @@ void FixNVETri::init()
   int i,itype;
 
   if (domain->dimension != 3)
-    error->all(FLERR,"Fix nve/line can only be used for 3d simulations");
+    error->all(FLERR,"Fix nve/tri can only be used for 3d simulations");
 
   // check that all particles are triangles
   // no point particles allowed
diff --git a/src/ASPHERE/fix_nve_tri.h b/src/ASPHERE/fix_nve_tri.h
index d676a140d62c5f101a2c14e0d637a1c76874fba2..a3877a938fcfef9b8199f2fdd49fb0f74ad12e5d 100644
--- a/src/ASPHERE/fix_nve_tri.h
+++ b/src/ASPHERE/fix_nve_tri.h
@@ -53,14 +53,14 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Fix nve/tri requires atom style tri
 
-UNDOCUMENTED
+Self-explanatory.
 
-E: Fix nve/line can only be used for 3d simulations
+E: Fix nve/tri can only be used for 3d simulations
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nve/tri requires tri particles
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/ASPHERE/pair_gayberne.h b/src/ASPHERE/pair_gayberne.h
index 64db9f4f79f1ab37f3b360016c6c2915dddd93c9..1fa0a8a0e7790028034f4ab4b9ef1a8d05f30202 100755
--- a/src/ASPHERE/pair_gayberne.h
+++ b/src/ASPHERE/pair_gayberne.h
@@ -78,7 +78,7 @@ class PairGayBerne : public Pair {
 
 E: Pair gayberne requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Illegal ... command
 
@@ -92,7 +92,7 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair gayberne requires atoms with same type have same shape
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair gayberne epsilon a,b,c coeffs are not all set
 
@@ -101,6 +101,6 @@ have these 3 coefficients set at least once.
 
 E: Bad matrix inversion in mldivide3
 
-UNDOCUMENTED
+This error should not occur unless the matrix is badly formed.
 
 */
diff --git a/src/ASPHERE/pair_line_lj.h b/src/ASPHERE/pair_line_lj.h
index a23c741eb1d4f444f0095734fffb8921e775b907..b6c2d3bc0b3dbb66c662396ed1d1cf408ee029e7 100644
--- a/src/ASPHERE/pair_line_lj.h
+++ b/src/ASPHERE/pair_line_lj.h
@@ -64,7 +64,7 @@ class PairLineLJ : public Pair {
 
 E: Pair line/lj requires atom style line
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Illegal ... command
 
diff --git a/src/ASPHERE/pair_resquared.cpp b/src/ASPHERE/pair_resquared.cpp
index 9fb782b681f1138f262f390c4794229567a32884..c2654ca7fd7689edb685e3fb421820a2918f63d1 100755
--- a/src/ASPHERE/pair_resquared.cpp
+++ b/src/ASPHERE/pair_resquared.cpp
@@ -328,7 +328,7 @@ void PairRESquared::init_style()
 
   for (int i = 1; i <= atom->ntypes; i++) {
     if (!atom->shape_consistency(i,shape1[i][0],shape1[i][1],shape1[i][2]))
-      error->all(FLERR,"Pair gayberne requires atoms with same type have same shape");
+      error->all(FLERR,"Pair resquared requires atoms with same type have same shape");
     if (setwell[i]) {
       shape2[i][0] = shape1[i][0]*shape1[i][0];
       shape2[i][1] = shape1[i][1]*shape1[i][1];
diff --git a/src/ASPHERE/pair_resquared.h b/src/ASPHERE/pair_resquared.h
index 7e69ce6eb0e461feed33169a7db501ce3d39b6df..da0b24a8b8e6eb9d0b366bd5ec2bf6a9378fa7fa 100755
--- a/src/ASPHERE/pair_resquared.h
+++ b/src/ASPHERE/pair_resquared.h
@@ -100,7 +100,7 @@ class PairRESquared : public Pair {
 
 E: Pair resquared requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Illegal ... command
 
@@ -112,9 +112,9 @@ E: Incorrect args for pair coefficients
 
 Self-explanatory.  Check the input script or data file.
 
-E: Pair gayberne requires atoms with same type have same shape
+E: Pair resquared requires atoms with same type have same shape
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair resquared epsilon a,b,c coeffs are not all set
 
@@ -126,6 +126,6 @@ Self-explanatory.
 
 E: Bad matrix inversion in mldivide3
 
-UNDOCUMENTED
+This error should not occur unless the matrix is badly formed.
 
 */
diff --git a/src/ASPHERE/pair_tri_lj.h b/src/ASPHERE/pair_tri_lj.h
index 97c7ad4a2dbd0f3752d4ab4a4a14b6204eb708e7..df65b0fd1000e5ed83880274666ff542896e3ddf 100644
--- a/src/ASPHERE/pair_tri_lj.h
+++ b/src/ASPHERE/pair_tri_lj.h
@@ -64,7 +64,7 @@ class PairTriLJ : public Pair {
 
 E: Pair tri/lj requires atom style tri
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Illegal ... command
 
diff --git a/src/CLASS2/dihedral_class2.h b/src/CLASS2/dihedral_class2.h
index cc1f13674ea7e7284bd5eb72ceb546ef1cf6c819..66173efaea8b88fdf72858a52419356f45e9b328 100644
--- a/src/CLASS2/dihedral_class2.h
+++ b/src/CLASS2/dihedral_class2.h
@@ -60,7 +60,7 @@ class DihedralClass2 : public Dihedral {
 W: Dihedral problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed dihedral atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Invalid coeffs for this dihedral style
 
diff --git a/src/CLASS2/improper_class2.h b/src/CLASS2/improper_class2.h
index 58508fda14222b72e2776fb1eed60224425dec6f..1e47b407c4a66b9ffca9ebaa396c137093878f5a 100644
--- a/src/CLASS2/improper_class2.h
+++ b/src/CLASS2/improper_class2.h
@@ -55,7 +55,7 @@ class ImproperClass2 : public Improper {
 W: Improper problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed improper atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for improper coefficients
 
diff --git a/src/COLLOID/fix_wall_colloid.h b/src/COLLOID/fix_wall_colloid.h
index 9e9ff0445bf13441be3a1f2769159e10e0ae0837..03e3b9e88f2eb0311ef217e2d04cf29d99dfc2b0 100644
--- a/src/COLLOID/fix_wall_colloid.h
+++ b/src/COLLOID/fix_wall_colloid.h
@@ -44,11 +44,11 @@ class FixWallColloid : public FixWall {
 
 E: Fix wall/colloid requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix wall/colloid requires extended particles
 
-Self-explanatory.
+One of the particles has radius 0.0.
 
 E: Particle on or inside fix wall surface
 
diff --git a/src/COLLOID/pair_yukawa_colloid.h b/src/COLLOID/pair_yukawa_colloid.h
index 57beb37550ac38d43cafb6c1d9c28f58785bb000..29d5b6521f55b8bac7a8c180123859b2166d0968 100644
--- a/src/COLLOID/pair_yukawa_colloid.h
+++ b/src/COLLOID/pair_yukawa_colloid.h
@@ -43,10 +43,10 @@ class PairYukawaColloid : public PairYukawa {
 
 E: Pair yukawa/colloid requires atom style sphere
 
-UNDOCUMENTED
+Self-explantory.
 
 E: Pair yukawa/colloid requires atoms with same type have same radius
 
-UNDOCUMENTED
+Self-explantory.
 
 */
diff --git a/src/DIPOLE/pair_dipole_cut.h b/src/DIPOLE/pair_dipole_cut.h
index fbd8df64f6fecb3d23f197eac0f4b5ae4fb9e894..f787dda55d4a57e17f5da2250f21ca5739909e5e 100644
--- a/src/DIPOLE/pair_dipole_cut.h
+++ b/src/DIPOLE/pair_dipole_cut.h
@@ -65,6 +65,6 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair dipole/cut requires atom attributes q, mu, torque
 
-UNDOCUMENTED
+The atom style defined does not have these attributes.
 
 */
diff --git a/src/FLD/pair_brownian.h b/src/FLD/pair_brownian.h
index cc3f672e87ba36ca7727daed0a34ffca5613e986..56a0b99e78deaff44a208761e8e9bff38679b1c9 100644
--- a/src/FLD/pair_brownian.h
+++ b/src/FLD/pair_brownian.h
@@ -71,18 +71,18 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair brownian requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 W: Pair brownian needs newton pair on for momentum conservation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair brownian requires extended particles
 
-UNDOCUMENTED
+One of the particles has radius 0.0.
 
 E: Pair brownian requires monodisperse particles
 
-UNDOCUMENTED
+All particles must be the same finite size.
 
 */
diff --git a/src/FLD/pair_brownian_poly.h b/src/FLD/pair_brownian_poly.h
index 90a1e7033c553ff64ad6c7253269b2074e771c80..98dd18ce5cb6bc9dd18a6b39076c01a45eb73409 100644
--- a/src/FLD/pair_brownian_poly.h
+++ b/src/FLD/pair_brownian_poly.h
@@ -42,14 +42,14 @@ class PairBrownianPoly : public PairBrownian {
 
 E: Pair brownian/poly requires newton pair off
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair brownian/poly requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair brownian/poly requires extended particles
 
-UNDOCUMENTED
+One of the particles has radius 0.0.
 
 */
diff --git a/src/FLD/pair_lubricate.h b/src/FLD/pair_lubricate.h
index b79d2333dcba2207da56e19e2a84d86fc018dd74..e78db0f66f052f934be180acc08842606683b77b 100644
--- a/src/FLD/pair_lubricate.h
+++ b/src/FLD/pair_lubricate.h
@@ -72,7 +72,7 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair lubricate requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair lubricate requires ghost atoms store velocity
 
@@ -80,10 +80,10 @@ Use the communicate vel yes command to enable this.
 
 E: Pair lubricate requires monodisperse particles
 
-UNDOCUMENTED
+All particles must be the same finite size.
 
 E: Using pair lubricate with inconsistent fix deform remap option
 
-UNDOCUMENTED
+If fix deform is used, the remap v option is required.
 
 */
diff --git a/src/FLD/pair_lubricateU.h b/src/FLD/pair_lubricateU.h
index 8cedc76dbc8e633cbfee1c78f33b1595c77a97c4..2b5a6209797ca624e6e656fabc7333260a7cb956 100644
--- a/src/FLD/pair_lubricateU.h
+++ b/src/FLD/pair_lubricateU.h
@@ -87,14 +87,14 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair lubricateU requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair lubricateU requires ghost atoms store velocity
 
-UNDOCUMENTED
+Use the communicate vel yes command to enable this.
 
 E: Pair lubricateU requires monodisperse particles
 
-UNDOCUMENTED
+All particles must be the same finite size.
 
 */
diff --git a/src/FLD/pair_lubricateU_poly.h b/src/FLD/pair_lubricateU_poly.h
index 8eb8cc2287368941848fe9ed2ed03023d58d56e2..9be965664c76b99e1327d8a641c7c276780e2de9 100644
--- a/src/FLD/pair_lubricateU_poly.h
+++ b/src/FLD/pair_lubricateU_poly.h
@@ -54,18 +54,18 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Pair lubricateU/poly requires newton pair off
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair lubricateU/poly requires ghost atoms store velocity
 
-UNDOCUMENTED
+Use the communicate vel yes command to enable this.
 
 E: Pair lubricate/poly requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair lubricate/poly requires extended particles
 
-UNDOCUMENTED
+One of the particles has radius 0.0.
 
 */
diff --git a/src/FLD/pair_lubricate_poly.h b/src/FLD/pair_lubricate_poly.h
index f4be3abee5f0681304d2978a94066ebc313e5f61..0a31137dd35b3ef40678665cb1dd114c985e5161 100644
--- a/src/FLD/pair_lubricate_poly.h
+++ b/src/FLD/pair_lubricate_poly.h
@@ -41,22 +41,22 @@ class PairLubricatePoly : public PairLubricate {
 
 E: Pair lubricate/poly requires newton pair off
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair lubricate/poly requires ghost atoms store velocity
 
-UNDOCUMENTED
+Use the communicate vel yes command to enable this.
 
 E: Pair lubricate/poly requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair lubricate/poly requires extended particles
 
-UNDOCUMENTED
+One of the particles has radius 0.0.
 
 E: Using pair lubricate/poly with inconsistent fix deform remap option
 
-UNDOCUMENTED
+If fix deform is used, the remap v option is required.
 
 */
diff --git a/src/GPU/fix_gpu.h b/src/GPU/fix_gpu.h
index b21310cb5b9ce0aa803bec5e7b30a47a5150cadf..d9856102f7620e59d41b562387b2d50352e957a8 100644
--- a/src/GPU/fix_gpu.h
+++ b/src/GPU/fix_gpu.h
@@ -50,7 +50,8 @@ class FixGPU : public Fix {
 
 E: Cannot use fix GPU with USER-CUDA mode enabled
 
-UNDOCUMENTED
+You cannot use both the GPU and USER-CUDA packages
+together.  Use one or the other.
 
 E: Illegal ... command
 
@@ -65,11 +66,12 @@ in LAMMPS.
 
 E: Cannot use force/hybrid_neigh with triclinic box
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: No OpenMP support compiled in
 
-UNDOCUMENTED
+An OpenMP flag is set, but LAMMPS was not built with
+OpenMP support.
 
 E: Cannot use pair hybrid with GPU neighbor builds
 
@@ -77,7 +79,7 @@ See documentation for fix gpu.
 
 E: Fix GPU split must be positive for hybrid pair styles
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot use neigh_modify exclude with GPU neighbor builds
 
diff --git a/src/GPU/gpu_extra.h b/src/GPU/gpu_extra.h
index e3bba976448ff42b796af19912c39929ed493336..2f4cdcb2ca4e6a50918a1773c3c459b03ddfe859 100644
--- a/src/GPU/gpu_extra.h
+++ b/src/GPU/gpu_extra.h
@@ -56,8 +56,52 @@ namespace GPU_EXTRA {
   inline void gpu_ready(LAMMPS_NS::Modify *modify, LAMMPS_NS::Error *error) {
     int ifix = modify->find_fix("package_gpu");
     if (ifix < 0)
-      error->all(FLERR,"The 'package gpu' command is required for /gpu styles");
+      error->all(FLERR,"The package gpu command is required for gpu styles");
   };
 }
 
 #endif
+
+/* ERROR/WARNING messages:
+
+E: Accelerated style in input script but no fix gpu
+
+UNDOCUMENTED
+
+E: Could not find/initialize a specified accelerator device
+
+UNDOCUMENTED
+
+E: Insufficient memory on accelerator
+
+UNDOCUMENTED
+
+E: GPU library not compiled for this accelerator
+
+UNDOCUMENTED
+
+E: Double precision is not supported on this accelerator
+
+UNDOCUMENTED
+
+E: Unable to initialize accelerator for use
+
+UNDOCUMENTED
+
+E: Accelerator sharing is not currently supported on system
+
+UNDOCUMENTED
+
+E: GPU particle split must be set to 1 for this pair style.
+
+UNDOCUMENTED
+
+E: Unknown error in GPU library
+
+UNDOCUMENTED
+
+E: The package gpu command is required for gpu styles
+
+UNDOCUMENTED
+
+*/
diff --git a/src/GPU/pair_buck_coul_cut_gpu.h b/src/GPU/pair_buck_coul_cut_gpu.h
index a92860d888699f2152e1f6249b90c293816912e8..1f482e113ab2de0eb2165f821fd53e36f31f2f16 100644
--- a/src/GPU/pair_buck_coul_cut_gpu.h
+++ b/src/GPU/pair_buck_coul_cut_gpu.h
@@ -49,14 +49,11 @@ class PairBuckCoulCutGPU : public PairBuckCoulCut {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with buck/coul/cut/gpu pair style
 
-UNDOCUMENTED
-
-U: Pair style buck/coul/cut/gpu requires atom attribute q
-
-The atom style defined does not have this attribute.
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_buck_coul_long_gpu.h b/src/GPU/pair_buck_coul_long_gpu.h
index ae39314398a14ba6d7cdd896e52e03d74b06d1ce..92918cedea64cbde35cd9c1d9263912ec5b8f89e 100644
--- a/src/GPU/pair_buck_coul_long_gpu.h
+++ b/src/GPU/pair_buck_coul_long_gpu.h
@@ -49,7 +49,8 @@ class PairBuckCoulLongGPU : public PairBuckCoulLong {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style buck/coul/long/gpu requires atom attribute q
 
@@ -57,10 +58,11 @@ The atom style defined does not have this attribute.
 
 E: Cannot use newton pair with buck/coul/long/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair style is incompatible with KSpace style
 
-UNDOCUMENTED
+If a pair style with a long-range Coulombic component is selected,
+then a kspace style must also be used.
 
 */
diff --git a/src/GPU/pair_buck_gpu.h b/src/GPU/pair_buck_gpu.h
index cef24eeccc5b7c581d3dc3a4c84c1739dfff67dc..0498755ca8e2c7898a79cf61f44ccf5d52522bba 100644
--- a/src/GPU/pair_buck_gpu.h
+++ b/src/GPU/pair_buck_gpu.h
@@ -49,10 +49,11 @@ class PairBuckGPU : public PairBuck {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with buck/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_coul_long_gpu.h b/src/GPU/pair_coul_long_gpu.h
index b15f732ec7772cbd4745c30a4868d98c7a5fef76..52744727783c932a9fc276bc1b43bbe1bcd8eb29 100644
--- a/src/GPU/pair_coul_long_gpu.h
+++ b/src/GPU/pair_coul_long_gpu.h
@@ -49,15 +49,16 @@ class PairCoulLongGPU : public PairCoulLong {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style coul/long/gpu requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have these attributes.
 
 E: Cannot use newton pair with coul/long/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair style is incompatible with KSpace style
 
diff --git a/src/GPU/pair_eam_alloy_gpu.h b/src/GPU/pair_eam_alloy_gpu.h
index ffa2af76aa0bc06b59d9985dec4c50b9aca2c2be..3305a4ea2433710cf4b2b9041ba1969c6f97e787 100644
--- a/src/GPU/pair_eam_alloy_gpu.h
+++ b/src/GPU/pair_eam_alloy_gpu.h
@@ -44,18 +44,20 @@ public:
 
 E: Incorrect args for pair coefficients
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script or data file.
 
 E: No matching element in EAM potential file
 
-UNDOCUMENTED
+The EAM potential file does not contain elements that match the
+requested elements.
 
 E: Cannot open EAM potential file %s
 
-UNDOCUMENTED
+The specified EAM potential file cannot be opened.  Check that the
+path and name are correct.
 
 E: Incorrect element names in EAM potential file
 
-UNDOCUMENTED
+The element names in the EAM file do not match those requested.
 
 */
diff --git a/src/GPU/pair_eam_fs_gpu.h b/src/GPU/pair_eam_fs_gpu.h
index c46226bcbfdff4066dd8a3543921f71e7ecacf4c..49733e57396fd3fb557083bfc0164fb685688aed 100644
--- a/src/GPU/pair_eam_fs_gpu.h
+++ b/src/GPU/pair_eam_fs_gpu.h
@@ -44,18 +44,20 @@ public:
 
 E: Incorrect args for pair coefficients
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script or data file.
 
 E: No matching element in EAM potential file
 
-UNDOCUMENTED
+The EAM potential file does not contain elements that match the
+requested elements.
 
 E: Cannot open EAM potential file %s
 
-UNDOCUMENTED
+The specified EAM potential file cannot be opened.  Check that the
+path and name are correct.
 
 E: Incorrect element names in EAM potential file
 
-UNDOCUMENTED
+The element names in the EAM file do not match those requested.
 
 */
diff --git a/src/GPU/pair_eam_gpu.h b/src/GPU/pair_eam_gpu.h
index 3415f9791436b5c463fdeaeefaebca03563b9d45..686f276e8b1d50238b3c22b9e446d765e8abb58c 100644
--- a/src/GPU/pair_eam_gpu.h
+++ b/src/GPU/pair_eam_gpu.h
@@ -56,11 +56,12 @@ class PairEAMGPU : public PairEAM {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with eam/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Not allocate memory eam/gpu pair style
 
diff --git a/src/GPU/pair_gayberne_gpu.cpp b/src/GPU/pair_gayberne_gpu.cpp
index 18c9f6356db68031d729e8469234581bc87ccbec..8447169abbfc4d03a52448d722279b447bcdbe3b 100644
--- a/src/GPU/pair_gayberne_gpu.cpp
+++ b/src/GPU/pair_gayberne_gpu.cpp
@@ -74,7 +74,7 @@ PairGayBerneGPU::PairGayBerneGPU(LAMMPS *lmp) : PairGayBerne(lmp),
 {
   avec = (AtomVecEllipsoid *) atom->style_match("ellipsoid");
   if (!avec) 
-    error->all(FLERR,"Pair gayberne requires atom style ellipsoid");
+    error->all(FLERR,"Pair gayberne/gpu requires atom style ellipsoid");
   quat_nmax = 0;
   quat = NULL;
   GPU_EXTRA::gpu_ready(lmp->modify, lmp->error); 
diff --git a/src/GPU/pair_gayberne_gpu.h b/src/GPU/pair_gayberne_gpu.h
index 5e182f5127c79d6400fa118b1f17b772e0c29089..8a249c1da63e7a56a16db12c807ab0dd48f2d71c 100644
--- a/src/GPU/pair_gayberne_gpu.h
+++ b/src/GPU/pair_gayberne_gpu.h
@@ -49,24 +49,21 @@ class PairGayBerneGPU : public PairGayBerne {
 
 /* ERROR/WARNING messages:
 
-E: Pair gayberne requires atom style ellipsoid
+E: Pair gayberne/gpu requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with gayberne/gpu pair style
 
-UNDOCUMENTED
-
-E: Pair gayberne/gpu requires atom style ellipsoid
-
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair gayberne/gpu requires atoms with same type have same shape
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_lj96_cut_gpu.h b/src/GPU/pair_lj96_cut_gpu.h
index 992b2b8e2b7f7221a8109a9f34babbe274778f82..8fa4df7555887e6bdfa74cf7c36538c6080fe707 100644
--- a/src/GPU/pair_lj96_cut_gpu.h
+++ b/src/GPU/pair_lj96_cut_gpu.h
@@ -49,10 +49,11 @@ class PairLJ96CutGPU : public PairLJ96Cut {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with lj96/cut/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_lj_charmm_coul_long_gpu.h b/src/GPU/pair_lj_charmm_coul_long_gpu.h
index 96c2e2f1aceaeb664c63bd6da8cff2ee04fcc9a5..d4c56350fd96261ead6120c9a933f22334e2a4e1 100644
--- a/src/GPU/pair_lj_charmm_coul_long_gpu.h
+++ b/src/GPU/pair_lj_charmm_coul_long_gpu.h
@@ -49,15 +49,16 @@ class PairLJCharmmCoulLongGPU : public PairLJCharmmCoulLong {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style lj/charmm/coul/long/gpu requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 E: Cannot use newton pair with lj/charmm/coul/long/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair style is incompatible with KSpace style
 
diff --git a/src/GPU/pair_lj_class2_coul_long_gpu.h b/src/GPU/pair_lj_class2_coul_long_gpu.h
index 7c5136d358b449913b83166badfd9c8b946b8bba..891cee288409549133871b19396d54b51c133f28 100644
--- a/src/GPU/pair_lj_class2_coul_long_gpu.h
+++ b/src/GPU/pair_lj_class2_coul_long_gpu.h
@@ -49,15 +49,16 @@ class PairLJClass2CoulLongGPU : public PairLJClass2CoulLong {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style lj/class2/coul/long/gpu requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 E: Cannot use newton pair with lj/class2/coul/long/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair style is incompatible with KSpace style
 
diff --git a/src/GPU/pair_lj_class2_gpu.h b/src/GPU/pair_lj_class2_gpu.h
index a7e286a147e2a31240f7c531b1c92aa153d54de5..64968a26eedebdf99abd417df1c8e2a3641c3d71 100644
--- a/src/GPU/pair_lj_class2_gpu.h
+++ b/src/GPU/pair_lj_class2_gpu.h
@@ -49,10 +49,11 @@ class PairLJClass2GPU : public PairLJClass2 {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with lj/class2/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_lj_cut_coul_cut_gpu.h b/src/GPU/pair_lj_cut_coul_cut_gpu.h
index 6deb28eaf1a545f3108993b5ae83404e9d043fde..c05a1377ce4ede50517c367ab7ac5b6c4f076810 100644
--- a/src/GPU/pair_lj_cut_coul_cut_gpu.h
+++ b/src/GPU/pair_lj_cut_coul_cut_gpu.h
@@ -49,14 +49,15 @@ class PairLJCutCoulCutGPU : public PairLJCutCoulCut {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style lj/cut/coul/cut/gpu requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 E: Cannot use newton pair with lj/cut/coul/cut/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_lj_cut_coul_long_gpu.h b/src/GPU/pair_lj_cut_coul_long_gpu.h
index 91a1784e82c26db003db033be63f7126dd7f304e..fe2355ca0f0372eb378d6dd17bb47d1c49af0e5c 100644
--- a/src/GPU/pair_lj_cut_coul_long_gpu.h
+++ b/src/GPU/pair_lj_cut_coul_long_gpu.h
@@ -49,15 +49,16 @@ class PairLJCutCoulLongGPU : public PairLJCutCoulLong {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style lj/cut/coul/long/gpu requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 E: Cannot use newton pair with lj/cut/coul/long/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair style is incompatible with KSpace style
 
diff --git a/src/GPU/pair_lj_cut_gpu.h b/src/GPU/pair_lj_cut_gpu.h
index 93032a9720549d6cd5ee4c09cef0d37190788436..7186a0b4e0b93f2b3066fd89d20cc90b6330db18 100644
--- a/src/GPU/pair_lj_cut_gpu.h
+++ b/src/GPU/pair_lj_cut_gpu.h
@@ -49,10 +49,11 @@ class PairLJCutGPU : public PairLJCut {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with lj/cut/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_lj_expand_gpu.h b/src/GPU/pair_lj_expand_gpu.h
index 57e8135f4d164ad1b33a1e9ef2e093d0b4ced7a3..454e27f31a409dd6d7ac21a6573d2448cfc1e2ac 100644
--- a/src/GPU/pair_lj_expand_gpu.h
+++ b/src/GPU/pair_lj_expand_gpu.h
@@ -49,10 +49,11 @@ class PairLJExpandGPU : public PairLJExpand {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with lj/expand/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_lj_sdk_coul_long_gpu.h b/src/GPU/pair_lj_sdk_coul_long_gpu.h
index 2e5d928fb65759c3550b75c40c4169c7a4303ebc..ab1ac9e09dcbefd0d6fac73ff936340723deebe5 100644
--- a/src/GPU/pair_lj_sdk_coul_long_gpu.h
+++ b/src/GPU/pair_lj_sdk_coul_long_gpu.h
@@ -51,18 +51,20 @@ class PairLJSDKCoulLongGPU : public PairLJSDKCoulLong {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Pair style lj/sdk/coul/long/gpu requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 E: Cannot use newton pair with lj/sdk/coul/long/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair style is incompatible with KSpace style
 
-UNDOCUMENTED
+If a pair style with a long-range Coulombic component is selected,
+then a kspace style must also be used.
 
 */
diff --git a/src/GPU/pair_lj_sdk_gpu.h b/src/GPU/pair_lj_sdk_gpu.h
index 34df1dd14627aaa589fcf5f3c238405b702d639d..6138d40e7ec64b2606ced8739160e328bb6aa831 100644
--- a/src/GPU/pair_lj_sdk_gpu.h
+++ b/src/GPU/pair_lj_sdk_gpu.h
@@ -51,10 +51,11 @@ class PairLJSDKGPU : public PairLJSDK {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with lj/sdk/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_morse_gpu.h b/src/GPU/pair_morse_gpu.h
index 7567d18ce2684c7e00d47bec020ec5c5a912e7b4..aaa5597b753e1ad9b32786068c48d06eff6fa1af 100644
--- a/src/GPU/pair_morse_gpu.h
+++ b/src/GPU/pair_morse_gpu.h
@@ -49,10 +49,11 @@ class PairMorseGPU : public PairMorse {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with morse/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_resquared_gpu.cpp b/src/GPU/pair_resquared_gpu.cpp
index 566712ec4690e0f43a675d3209badb5e7570709a..56359c631162b0b303ba353ba4603c9b4cc192b2 100644
--- a/src/GPU/pair_resquared_gpu.cpp
+++ b/src/GPU/pair_resquared_gpu.cpp
@@ -73,7 +73,7 @@ PairRESquaredGPU::PairRESquaredGPU(LAMMPS *lmp) : PairRESquared(lmp),
 {
   avec = (AtomVecEllipsoid *) atom->style_match("ellipsoid");
   if (!avec) 
-    error->all(FLERR,"Pair gayberne requires atom style ellipsoid");
+    error->all(FLERR,"Pair resquared/gpu requires atom style ellipsoid");
   quat_nmax = 0;
   quat = NULL;
   GPU_EXTRA::gpu_ready(lmp->modify, lmp->error); 
diff --git a/src/GPU/pair_resquared_gpu.h b/src/GPU/pair_resquared_gpu.h
index 1e188cae6c5ce2c43fb8a965eb1a76e54e7bf925..3efacd97ea24e8eff8f7c97a57d8b6894b89f0a1 100644
--- a/src/GPU/pair_resquared_gpu.h
+++ b/src/GPU/pair_resquared_gpu.h
@@ -49,24 +49,21 @@ class PairRESquaredGPU : public PairRESquared {
 
 /* ERROR/WARNING messages:
 
-E: Pair gayberne requires atom style ellipsoid
+E: Pair resquared/gpu requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with resquared/gpu pair style
 
-UNDOCUMENTED
-
-E: Pair resquared/gpu requires atom style ellipsoid
-
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair resquared/gpu requires atoms with same type have same shape
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pair_table_gpu.h b/src/GPU/pair_table_gpu.h
index efe0edbb3dc5049a5cf20630c22fa00e25021dd3..b1a2de2a443f7de0c91b1bbe35be8c15f27f031c 100644
--- a/src/GPU/pair_table_gpu.h
+++ b/src/GPU/pair_table_gpu.h
@@ -49,15 +49,16 @@ class PairTableGPU : public PairTable {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with table/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair distance < table inner cutoff
 
-UNDOCUMENTED
+Two atoms are closer together than the pairwise table allows.
 
 E: Pair distance > table outer cutoff
 
diff --git a/src/GPU/pair_yukawa_gpu.h b/src/GPU/pair_yukawa_gpu.h
index d6f04fc2b764774ce3f6aa5aa28ff11fec21a7ad..b95d898344c24184650557253de1f8dee48f4abe 100644
--- a/src/GPU/pair_yukawa_gpu.h
+++ b/src/GPU/pair_yukawa_gpu.h
@@ -49,10 +49,11 @@ class PairYukawaGPU : public PairYukawa {
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Cannot use newton pair with yukawa/gpu pair style
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/GPU/pppm_gpu.h b/src/GPU/pppm_gpu.h
index c181420d0f455984e95c3618795b5cf1eb4cffc4..aec92bc60db8640a571086269d52479ca9f40745 100644
--- a/src/GPU/pppm_gpu.h
+++ b/src/GPU/pppm_gpu.h
@@ -1,4 +1,4 @@
-/* ----------------------------------------------------------------------
+ndoc/* ----------------------------------------------------------------------
    LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
    http://lammps.sandia.gov, Sandia National Laboratories
    Steve Plimpton, sjplimp@sandia.gov
@@ -67,11 +67,12 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Cannot use order greater than 8 with pppm/gpu.
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Out of memory on GPGPU
 
-UNDOCUMENTED
+GPU memory is limited.  Reduce the size of the problem or increase the
+number of GPUs.
 
 E: Out of range atoms - cannot compute PPPM
 
diff --git a/src/GRANULAR/fix_wall_gran.h b/src/GRANULAR/fix_wall_gran.h
index 51732c837a95b5ac1d40fde3dc09d0df4acb88d8..e240f33ba0195134731a7973b75329f05042851d 100644
--- a/src/GRANULAR/fix_wall_gran.h
+++ b/src/GRANULAR/fix_wall_gran.h
@@ -85,7 +85,7 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Fix wall/gran requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot use wall in periodic dimension
 
diff --git a/src/GRANULAR/pair_gran_hooke_history.h b/src/GRANULAR/pair_gran_hooke_history.h
index fea3713653f2d1fed8abadb8e229475f1a04a1bc..593143205c7dc3e76402b5e8fec23e527f3d33ae 100644
--- a/src/GRANULAR/pair_gran_hooke_history.h
+++ b/src/GRANULAR/pair_gran_hooke_history.h
@@ -80,7 +80,7 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair granular requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair granular requires ghost atoms store velocity
 
diff --git a/src/KIM/pair_kim.cpp b/src/KIM/pair_kim.cpp
index e210c67cd885ab57809449c3f0489c7687210663..465461ea9c5d59a636087a1e1acd7e3cf4439d8b 100644
--- a/src/KIM/pair_kim.cpp
+++ b/src/KIM/pair_kim.cpp
@@ -35,8 +35,6 @@
 
 using namespace LAMMPS_NS;
 
-
-
 /* ---------------------------------------------------------------------- */
 
 PairKIM::PairKIM(LAMMPS *lmp) : Pair(lmp)
@@ -298,7 +296,7 @@ void PairKIM::coeff(int narg, char **arg)
 void PairKIM::init_style()
 {
   if (force->newton_pair != 0)
-    error->all(FLERR,"Pair style pair_KIM requires newton pair Off");
+    error->all(FLERR,"Pair style kim requires newton pair off");
 
   // setup onebuf for neighbors of one atom if needed
 
@@ -460,14 +458,14 @@ int PairKIM::get_neigh(void **kimmdl,int *mode,int *request,
       self->pointsto =0;
       *numnei=0;
       return KIM_STATUS_NEIGH_ITER_INIT_OK; //succsesful restart
-    } else if(*request==1){//increment iterator
-      if (self->pointsto > inum || inum <0){
+    } else if (*request==1) { //increment iterator
+      if (self->pointsto > inum || inum <0) {
 	self->error->one(FLERR,"KIM neighbor iterator exceeded range");
-      }else if(self->pointsto == inum) {
+      } else if (self->pointsto == inum) {
 	self->pointsto ==0;
 	*numnei=0;
 	return KIM_STATUS_NEIGH_ITER_PAST_END; //reached end by iterator
-      }else{
+      } else{
 	*atom = ilist[self->pointsto];
 	*numnei = numneigh[*atom];
 
@@ -486,7 +484,7 @@ int PairKIM::get_neigh(void **kimmdl,int *mode,int *request,
 	if (*numnei > KIM_API_MAX_NEIGHBORS) 
 	  return KIM_STATUS_NEIGH_TOO_MANY_NEIGHBORS;
 	if (pkim->support_Rij){
-	  for( jj=0; jj < *numnei; jj++){
+	  for (jj=0; jj < *numnei; jj++){ 
 	    int i = *atom;
 	    j = (*nei1atom)[jj];
 	    self->Rij[jj*3 +0] = -x[i*3+0] + x[j*3+0];
@@ -531,10 +529,9 @@ int PairKIM::get_neigh(void **kimmdl,int *mode,int *request,
       }
     }
     return KIM_STATUS_OK;//successful end
-  }else{
-    return KIM_STATUS_NEIGH_INVALID_MODE;//invalid mode
-  }
-  return -16;//should not get here: unspecified error
+  } else return KIM_STATUS_NEIGH_INVALID_MODE;//invalid mode
+
+  return -16; //should not get here: unspecified error
 }
 
 /* ---------------------------------------------------------------------- */
diff --git a/src/KIM/pair_kim.h b/src/KIM/pair_kim.h
index aac9ad9beb434f4597c606da81ff4ea0672623dd..024c489825d4ac430796cdda0d081a9c9b1eb84f 100644
--- a/src/KIM/pair_kim.h
+++ b/src/KIM/pair_kim.h
@@ -117,34 +117,40 @@ class PairKIM : public Pair {
 
 E: Illegal ... command
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script syntax and compare to the
+documentation for the command.  You can use -echo screen as a
+command-line option when running LAMMPS to see the offending line.
 
 E: Incorrect args for pair coefficients
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script or data file.
 
-E: Pair style pair_KIM requires newton pair Off
+E: Pair style kim requires newton pair off
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: All pair coeffs are not set
 
-UNDOCUMENTED
+All pair coefficients must be set in the data file or by the
+pair_coeff command before running a simulation.
 
 E: KIM neighbor iterator exceeded range
 
-UNDOCUMENTED
+This error should not normally occur if the KIM library is working
+correctly.
 
 E: KIM_DIR environement variable is unset
 
-UNDOCUMENTED
+The KIM library requires that this environment variable be set before
+running LAMMPS>
 
 E: PWD environement variable is unset
 
-UNDOCUMENTED
+The KIM library requires that this environment variable be set before
+running LAMMPS>
 
 E: KIM initialization failed
 
-UNDOCUMENTED
+This is an error return from the KIM library.
 
 */
diff --git a/src/KSPACE/pppm_tip4p.h b/src/KSPACE/pppm_tip4p.h
index 6afb0ae036586482a358202eea06c40fc4de72f7..8031b706b615abd93c9a9d06909d823a91b31f00 100644
--- a/src/KSPACE/pppm_tip4p.h
+++ b/src/KSPACE/pppm_tip4p.h
@@ -48,7 +48,7 @@ class PPPMTIP4P : public PPPM {
 
 E: Kspace style pppm/tip4p requires newton on
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Out of range atoms - cannot compute PPPM
 
diff --git a/src/MANYBODY/pair_adp.h b/src/MANYBODY/pair_adp.h
index 3e68846e50f51b470be6c4db6fa722245079530a..6bd52e6d7d6144ff71e426431499765df93f7da1 100644
--- a/src/MANYBODY/pair_adp.h
+++ b/src/MANYBODY/pair_adp.h
@@ -107,14 +107,16 @@ Self-explanatory.  Check the input script or data file.
 
 E: No matching element in ADP potential file
 
-UNDOCUMENTED
+The ADP potential file does not contain elements that match the
+requested elements.
 
 E: Cannot open ADP potential file %s
 
-UNDOCUMENTED
+The specified ADP potential file cannot be opened.  Check that the
+path and name are correct.
 
 E: Incorrect element names in ADP potential file
 
-UNDOCUMENTED
+The element names in the ADP file do not match those requested.
 
 */
diff --git a/src/MOLECULE/bond_fene.h b/src/MOLECULE/bond_fene.h
index 88f50952c4f00dbe0785bc30602644fe3243c9bd..e90c61c0379e742e668bab80085df85059795dae 100644
--- a/src/MOLECULE/bond_fene.h
+++ b/src/MOLECULE/bond_fene.h
@@ -54,7 +54,7 @@ class BondFENE : public Bond {
 W: FENE bond too long: %ld %d %d %g
 
 A FENE bond has stretched dangerously far.  It's interaction strength
-will be truncated to attempt to prevent the bond from blowing up. :dd
+will be truncated to attempt to prevent the bond from blowing up.
 
 E: Bad FENE bond
 
@@ -72,6 +72,6 @@ Most FENE models need this setting for the special_bonds command.
 W: FENE bond too long: %ld %g
 
 A FENE bond has stretched dangerously far.  It's interaction strength
-will be truncated to attempt to prevent the bond from blowing up. :dd
+will be truncated to attempt to prevent the bond from blowing up.
 
 */
diff --git a/src/MOLECULE/bond_fene_expand.h b/src/MOLECULE/bond_fene_expand.h
index bae8a7327364613dfbbf0cdeefa4d60a713f42f8..449c32b308b9eff3f3e9977d5503cb58f055b2fa 100644
--- a/src/MOLECULE/bond_fene_expand.h
+++ b/src/MOLECULE/bond_fene_expand.h
@@ -54,7 +54,7 @@ class BondFENEExpand : public Bond {
 W: FENE bond too long: %ld %d %d %g
 
 A FENE bond has stretched dangerously far.  It's interaction strength
-will be truncated to attempt to prevent the bond from blowing up. :dd
+will be truncated to attempt to prevent the bond from blowing up.
 
 E: Bad FENE bond
 
@@ -72,6 +72,6 @@ Most FENE models need this setting for the special_bonds command.
 W: FENE bond too long: %ld %g
 
 A FENE bond has stretched dangerously far.  It's interaction strength
-will be truncated to attempt to prevent the bond from blowing up. :dd
+will be truncated to attempt to prevent the bond from blowing up.
 
 */
diff --git a/src/MOLECULE/dihedral_charmm.h b/src/MOLECULE/dihedral_charmm.h
index 44a93357f57405cd90d7086e2cac93c1194389fd..be0e7c58476e2c6889748885568e6d0ca6e56e44 100644
--- a/src/MOLECULE/dihedral_charmm.h
+++ b/src/MOLECULE/dihedral_charmm.h
@@ -54,7 +54,7 @@ class DihedralCharmm : public Dihedral {
 W: Dihedral problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed dihedral atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for dihedral coefficients
 
diff --git a/src/MOLECULE/dihedral_harmonic.h b/src/MOLECULE/dihedral_harmonic.h
index ce78bcd992a25f27bbd8575ec68327a45ec51ac6..5eafdb61f3cd16b2b0d066d3a5c4707715be7b31 100644
--- a/src/MOLECULE/dihedral_harmonic.h
+++ b/src/MOLECULE/dihedral_harmonic.h
@@ -51,7 +51,7 @@ class DihedralHarmonic : public Dihedral {
 W: Dihedral problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed dihedral atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for dihedral coefficients
 
diff --git a/src/MOLECULE/dihedral_helix.h b/src/MOLECULE/dihedral_helix.h
index 6f254ad948fa1330bf188896d56d3ce651e09132..f28b9db28e22369819124076044b3f61cce9e27e 100644
--- a/src/MOLECULE/dihedral_helix.h
+++ b/src/MOLECULE/dihedral_helix.h
@@ -50,7 +50,7 @@ class DihedralHelix : public Dihedral {
 W: Dihedral problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed dihedral atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for dihedral coefficients
 
diff --git a/src/MOLECULE/dihedral_multi_harmonic.h b/src/MOLECULE/dihedral_multi_harmonic.h
index 8ba96dc0c946c6a8244257f5fd0c6d257c4c0bf0..a768cb6d62521826611dc0d7af1a26ba11900392 100644
--- a/src/MOLECULE/dihedral_multi_harmonic.h
+++ b/src/MOLECULE/dihedral_multi_harmonic.h
@@ -50,7 +50,7 @@ class DihedralMultiHarmonic : public Dihedral {
 W: Dihedral problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed dihedral atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for dihedral coefficients
 
diff --git a/src/MOLECULE/dihedral_opls.h b/src/MOLECULE/dihedral_opls.h
index 887507324e5a6fa2597909631d8449ec5b65a583..e2c0d6b2c4f1f0d6953c88ab0038cc9ed1232e77 100644
--- a/src/MOLECULE/dihedral_opls.h
+++ b/src/MOLECULE/dihedral_opls.h
@@ -50,7 +50,7 @@ class DihedralOPLS : public Dihedral {
 W: Dihedral problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed dihedral atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for dihedral coefficients
 
diff --git a/src/MOLECULE/improper_cvff.h b/src/MOLECULE/improper_cvff.h
index 410522952fc37cfeb19e6e2bcdc87835a13bf8f3..5f8755b30cbd749410dd22c7fd3f1949df331be5 100644
--- a/src/MOLECULE/improper_cvff.h
+++ b/src/MOLECULE/improper_cvff.h
@@ -51,7 +51,7 @@ class ImproperCvff : public Improper {
 W: Improper problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed improper atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for improper coefficients
 
diff --git a/src/MOLECULE/improper_harmonic.h b/src/MOLECULE/improper_harmonic.h
index 5e5c0bf22a3d0dd9f24a21920834ef073ff2626b..f75df37dc562c820b3b3b660d85f839375066614 100644
--- a/src/MOLECULE/improper_harmonic.h
+++ b/src/MOLECULE/improper_harmonic.h
@@ -50,7 +50,7 @@ class ImproperHarmonic : public Improper {
 W: Improper problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed improper atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for improper coefficients
 
diff --git a/src/MOLECULE/improper_umbrella.h b/src/MOLECULE/improper_umbrella.h
index 6a566d606d213d4f27b70b59af68a694716c3de6..fd3d47127f581049dc8c486693ae793faa06f252 100644
--- a/src/MOLECULE/improper_umbrella.h
+++ b/src/MOLECULE/improper_umbrella.h
@@ -50,7 +50,7 @@ class ImproperUmbrella : public Improper {
 W: Improper problem: %d %ld %d %d %d %d
 
 Conformation of the 4 listed improper atoms is extreme; you may want
-to check your simulation geometry. :dd
+to check your simulation geometry.
 
 E: Incorrect args for improper coefficients
 
diff --git a/src/PERI/pair_peri_lps.h b/src/PERI/pair_peri_lps.h
index 3d382acdf6f520aed8c7759cac5d9bbfd138a3a7..aa2ab23c3b6486dc724b0dd061d27c3190985056 100644
--- a/src/PERI/pair_peri_lps.h
+++ b/src/PERI/pair_peri_lps.h
@@ -83,7 +83,7 @@ pair_coeff command before running a simulation.
 
 E: Pair style peri requires atom style peri
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair peri requires an atom map, see atom_modify
 
diff --git a/src/PERI/pair_peri_pmb.h b/src/PERI/pair_peri_pmb.h
index 4b4d1a7646b6bc0fade957b50d6b9e92d53ea778..3a53351070218db6a67452dff45fbddcaebe1ab6 100644
--- a/src/PERI/pair_peri_pmb.h
+++ b/src/PERI/pair_peri_pmb.h
@@ -76,7 +76,7 @@ pair_coeff command before running a simulation.
 
 E: Pair style peri requires atom style peri
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Pair peri requires an atom map, see atom_modify
 
diff --git a/src/REPLICA/neb.h b/src/REPLICA/neb.h
index bc88426e4d6d6a3784a968f772bc63e292c5e551..02eac60495b6b244a46a382f9fb8664c7caa7bef 100644
--- a/src/REPLICA/neb.h
+++ b/src/REPLICA/neb.h
@@ -106,7 +106,7 @@ for NEB.
 
 E: Too many timesteps
 
-UNDOCUMENTED
+The cummulative timesteps must fit in a 64-bit integer.
 
 E: Incorrect format in NEB coordinate file
 
diff --git a/src/REPLICA/prd.h b/src/REPLICA/prd.h
index 69c3d38e55d2921e6aabd1a72cdfc6ebdbb9f857..0e5b4db5ca39be9be3582e813defb1d98b65a193 100644
--- a/src/REPLICA/prd.h
+++ b/src/REPLICA/prd.h
@@ -120,7 +120,7 @@ after the PRD simulation.
 
 E: Too many timesteps
 
-UNDOCUMENTED
+The cummulative timesteps must fit in a 64-bit integer.
 
 E: Cannot use PRD with a time-dependent fix defined
 
diff --git a/src/REPLICA/tad.h b/src/REPLICA/tad.h
index b9962ad5fa14c06804473ee3b92e71b161214a75..e5f1c38be8421f119366772df104208f0ef3fc9f 100644
--- a/src/REPLICA/tad.h
+++ b/src/REPLICA/tad.h
@@ -144,7 +144,7 @@ after the PRD simulation.
 
 E: Too many timesteps
 
-UNDOCUMENTED
+The cummulative timesteps must fit in a 64-bit integer.
 
 E: Too many iterations
 
diff --git a/src/REPLICA/temper.h b/src/REPLICA/temper.h
index abda20d76b2bc0749d2147da7411ec18183dc0aa..e61ee6711c08262d97b5d897919ccb8c66318f12 100644
--- a/src/REPLICA/temper.h
+++ b/src/REPLICA/temper.h
@@ -96,7 +96,7 @@ temperature (nvt or langevin).
 
 E: Too many timesteps
 
-UNDOCUMENTED
+The cummulative timesteps must fit in a 64-bit integer.
 
 E: Tempering could not find thermo_pe compute
 
diff --git a/src/REPLICA/verlet_split.h b/src/REPLICA/verlet_split.h
index c75b49d1a40f3a2fb53f1d132bf54ad186d1c360..2ad59a4d4d4a72ed81d603a6244a7f756f3cf94f 100644
--- a/src/REPLICA/verlet_split.h
+++ b/src/REPLICA/verlet_split.h
@@ -57,18 +57,20 @@ class VerletSplit : public Verlet {
 
 E: Verlet/split requires 2 partitions
 
-UNDOCUMENTED
+See the -partition command-line switch.
 
 E: Verlet/split requires Rspace partition size be multiple of Kspace partition size
 
-UNDOCUMENTED
+This is so there is an equal number of Rspace processors for every
+Kspace processor.
 
 E: Verlet/split requires Rspace partition layout be multiple of Kspace partition layout in each dim
 
-UNDOCUMENTED
+This is controlled by the processors command.
 
 W: No Kspace calculation with verlet/split
 
-UNDOCUMENTED
+The 2nd partition performs a kspace calculation so the kspace_style
+command must be used.
 
 */
diff --git a/src/SRD/fix_srd.cpp b/src/SRD/fix_srd.cpp
index d18f2bab9be014ad5dfd4621443a6d82aa022bd6..7cbb604a492299c92df657e86a36a9fe3fcd22e5 100644
--- a/src/SRD/fix_srd.cpp
+++ b/src/SRD/fix_srd.cpp
@@ -1190,13 +1190,13 @@ void FixSRD::collisions_single()
 		sprintf(str,
 			"SRD particle %d started "
 			"inside big particle %d on step " BIGINT_FORMAT 
-			" bounce %d\n",
+			" bounce %d",
 			atom->tag[i],atom->tag[j],update->ntimestep,ibounce+1);
 	      else
 		sprintf(str,
 			"SRD particle %d started "
 			"inside big particle %d on step " BIGINT_FORMAT 
-			" bounce %d\n",
+			" bounce %d",
 			atom->tag[i],atom->tag[j],update->ntimestep,ibounce+1);
 	      if (insideflag == INSIDE_ERROR) error->one(FLERR,str);
 	      error->warning(FLERR,str);
@@ -1344,7 +1344,7 @@ void FixSRD::collisions_multi()
 	      sprintf(str,
 		      "SRD particle %d started "
 		      "inside big particle %d on step " BIGINT_FORMAT 
-		      " bounce %d\n",
+		      " bounce %d",
 		      atom->tag[i],atom->tag[j],update->ntimestep,ibounce+1);
 	      if (insideflag == INSIDE_ERROR) error->one(FLERR,str);
 	      error->warning(FLERR,str);
diff --git a/src/SRD/fix_srd.h b/src/SRD/fix_srd.h
index a3266ae9f49f3532a9d69ebee320faa568e5378e..4d72e1badebedb8522c96f15ab61c49451d53e2c 100644
--- a/src/SRD/fix_srd.h
+++ b/src/SRD/fix_srd.h
@@ -298,7 +298,8 @@ deform needs to be used.
 
 W: Using fix srd with box deformation but no SRD thermostat
 
-UNDOCUMENTED
+The deformation will heat the SRD particles so this can
+be dangerous.
 
 W: Fix srd SRD moves may trigger frequent reneighboring
 
@@ -328,17 +329,23 @@ E: Fix SRD: bad bin assignment for SRD advection
 Something has gone wrong in your SRD model; try using more
 conservative settings.
 
-E: SRD particle %d started inside big particle %d on step %ld bounce %d\n
+E: SRD particle %d started inside big particle %d on step %ld bounce %d
 
-UNDOCUMENTED
+See the inside keyword if you want this message to be an error vs
+warning.
+
+W: SRD particle %d started inside big particle %d on step %ld bounce %d
+
+See the inside keyword if you want this message to be an error vs
+warning.
 
 E: Bad quadratic solve for particle/line collision
 
-UNDOCUMENTED
+This is an internal error.  It should nornally not occur.
 
 E: Bad quadratic solve for particle/tri collision
 
-UNDOCUMENTED
+This is an internal error.  It should nornally not occur.
 
 W: Fix srd particle moved outside valid domain
 
@@ -350,11 +357,11 @@ Big particles must be extended spheriods or ellipsoids.
 
 E: Cannot use lines with fix srd unless overlap is set
 
-UNDOCUMENTED
+This is because line segements are connected to each other.
 
 E: Cannot use tris with fix srd unless overlap is set
 
-UNDOCUMENTED
+This is because triangles are connected to each other.
 
 E: Fix srd requires SRD particles all have same mass
 
@@ -366,11 +373,23 @@ This is not allowed.  Make your SRD bin size smaller.
 
 E: SRD bins for fix srd are not cubic enough
 
-The bin shape is not within tolerance of cubic.
+The bin shape is not within tolerance of cubic.  See the cubic
+keyword if you want this message to be an error vs warning.
+
+W: SRD bins for fix srd are not cubic enough
+
+The bin shape is not within tolerance of cubic.  See the cubic
+keyword if you want this message to be an error vs warning.
 
 E: SRD bin size for fix srd differs from user request
 
-Fix SRD had to adjust the bin size to fit the simulation box.
+Fix SRD had to adjust the bin size to fit the simulation box.  See the
+cubic keyword if you want this message to be an error vs warning.
+
+W: SRD bin size for fix srd differs from user request
+
+Fix SRD had to adjust the bin size to fit the simulation box.  See the
+cubic keyword if you want this message to be an error vs warning.
 
 E: Fix srd lamda must be >= 0.6 of SRD grid size
 
diff --git a/src/atom.h b/src/atom.h
index 6ddd280f0195b020f0f2b34fbd0706ae9abab366..111761884b0cfb14fc8327e64c62cb77131c4213 100644
--- a/src/atom.h
+++ b/src/atom.h
@@ -277,11 +277,13 @@ atoms.
 
 E: Incorrect bonus data format in data file
 
-UNDOCUMENTED
+See the read_data doc page for a description of how various kinds of
+bonus data must be formatted for certain atom styles.
 
 E: Invalid atom ID in Bonus section of data file
 
-UNDOCUMENTED
+Atom IDs must be positive integers and within range of defined
+atoms.
 
 E: Invalid atom ID in Bonds section of data file
 
diff --git a/src/atom_vec_ellipsoid.h b/src/atom_vec_ellipsoid.h
index 36244ad8158f23dae2690688b41db5e4e0cb3b9d..2e2e13fbbbbbc90184b05f2fac730f94867c5c75 100755
--- a/src/atom_vec_ellipsoid.h
+++ b/src/atom_vec_ellipsoid.h
@@ -114,10 +114,10 @@ Density value cannot be <= 0.0.
 
 E: Assigning ellipsoid parameters to non-ellipsoid atom
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid shape in Ellipsoids section of data file
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/atom_vec_line.cpp b/src/atom_vec_line.cpp
index c49cd6b6ad4d88bdfb9269538bbfa4c0ce9af53b..f98170533c973ef017c6b7e391d4ad6b30cd99ea 100644
--- a/src/atom_vec_line.cpp
+++ b/src/atom_vec_line.cpp
@@ -1154,17 +1154,16 @@ void AtomVecLine::consistency_check(int n, char *str)
   }
 
   if (iflag) {
-    char msg[128];
-    sprintf(msg,"BAD VECLINE PTRS: %s: %d %d: %d\n",str,comm->me,
-	    update->ntimestep,iflag);
-    error->one(FLERR,msg);
+    printf("BAD vecline ptrs: %s: %d %d: %d\n",str,comm->me,
+	   update->ntimestep,iflag);
+    MPI_Abort(world,1);
   }
 
   if (count != nlocal_bonus) {
     char msg[128];
-    sprintf(msg,"BAD VECLINE COUNT: %s: %d %d: %d %d\n",
-	    str,comm->me,update->ntimestep,count,nlocal_bonus);
-    error->one(FLERR,msg);
+    printf("BAD vecline count: %s: %d %d: %d %d\n",
+           str,comm->me,update->ntimestep,count,nlocal_bonus);
+    MPI_Abort(world,1);
   }
 }
 */
diff --git a/src/atom_vec_line.h b/src/atom_vec_line.h
index ca35e9be469d17d18d82ffde1fb9b5ef131f3901..38b7aee79b05f3c7db1702445903bb4ee4b3677a 100644
--- a/src/atom_vec_line.h
+++ b/src/atom_vec_line.h
@@ -99,7 +99,7 @@ class AtomVecLine : public AtomVec {
 
 E: Atom_style line can only be used in 2d simulations
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Per-processor system is too big
 
@@ -120,18 +120,11 @@ Density value cannot be <= 0.0.
 
 E: Assigning line parameters to non-line atom
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Inconsistent line segment in data file
 
-UNDOCUMENTED
-
-E: BAD VECLINE PTRS: %s: %d %d: %d\n
-
-UNDOCUMENTED
-
-E: BAD VECLINE COUNT: %s: %d %d: %d %d\n
-
-UNDOCUMENTED
+The end points of the line segment are not equal distances from the
+center point which is the atom coordinate.
 
 */
diff --git a/src/atom_vec_tri.h b/src/atom_vec_tri.h
index 61368404e1b9fe788b095c2812c4518a5ba7e382..10a0743bd51b8a8d6320a0d53c326c9b405c3a04 100644
--- a/src/atom_vec_tri.h
+++ b/src/atom_vec_tri.h
@@ -100,7 +100,7 @@ class AtomVecTri : public AtomVec {
 
 E: Atom_style tri can only be used in 3d simulations
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Per-processor system is too big
 
@@ -121,18 +121,20 @@ Density value cannot be <= 0.0.
 
 E: Assigning tri parameters to non-tri atom
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid shape in Triangles section of data file
 
-UNDOCUMENTED
+Two or more of the triangle corners are duplicate points.
 
 E: Inconsistent triangle in data file
 
-UNDOCUMENTED
+The centroid of the triangle as defined by the corner points is not
+the atom coordinate.
 
 E: Insufficient Jacobi rotations for triangle
 
-UNDOCUMENTED
+The calculation of the intertia tensor of the triangle failed.  This
+should not happen if it is a reasonably shaped triangle.
 
 */
diff --git a/src/balance.cpp b/src/balance.cpp
index 45e64ef48f9af9784e2c17d61d8161eb447e144b..458b6df23c21bc1c2ec94a54f60978d9a685bb70 100644
--- a/src/balance.cpp
+++ b/src/balance.cpp
@@ -87,8 +87,6 @@ void Balance::command(int narg, char **arg)
 
   // parse arguments
 
-  if (narg < 1) error->all(FLERR,"Illegal balance command");
-
   int dimension = domain->dimension;
   int *procgrid = comm->procgrid;
   xflag = yflag = zflag = NONE;
diff --git a/src/balance.h b/src/balance.h
index c85a4b65c8e5fee7b48537e65b6bb105f3e4848f..16b62d896f183823b86979c48e16dcc89b2bc7cd 100644
--- a/src/balance.h
+++ b/src/balance.h
@@ -74,30 +74,34 @@ class Balance : protected Pointers {
 
 E: Balance command before simulation box is defined
 
-UNDOCUMENTED
+The balance command cannot be used before a read_data, read_restart,
+or create_box command.
 
 E: Illegal ... command
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script syntax and compare to the
+documentation for the command.  You can use -echo screen as a
+command-line option when running LAMMPS to see the offending line.
 
 E: Cannot balance in z dimension for 2d simulation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Balance dynamic string is invalid
 
-UNDOCUMENTED
+The string can only contain the characters "x", "y", or "z".
 
 E: Balance dynamic string is invalid for 2d simulation
 
-UNDOCUMENTED
+The string cannot contain the letter "z".
 
 E: Lost atoms via balance: original %ld current %ld
 
-UNDOCUMENTED
+This should not occur.  Report the problem to the developers.
 
 E: Cannot open balance output file
 
-UNDOCUMENTED
+This error message can only occur if debug options
+are uncommented in src/balance.cpp.
 
 */
diff --git a/src/change_box.cpp b/src/change_box.cpp
index a47be36665a220c78d4fa7d6bc83a928d897941c..2b629812cc4c38c5a108e6c9f6d9425b27a0a6fc 100644
--- a/src/change_box.cpp
+++ b/src/change_box.cpp
@@ -277,7 +277,8 @@ void ChangeBox::command(int narg, char **arg)
       domain->set_boundary(3,&arg[ops[i].boundindex],1);
       if (domain->dimension == 2 && domain->zperiodic == 0)
 	error->all(FLERR,
-		   "Cannot run 2d simulation with nonperiodic Z dimension");
+		   "Cannot change box z boundary to "
+		   "nonperiodic for a 2d simulation");
       domain->set_initial_box();
       domain->set_global_box();
       domain->set_local_box();
@@ -371,7 +372,7 @@ void ChangeBox::command(int narg, char **arg)
   bigint natoms;
   bigint nblocal = atom->nlocal;
   MPI_Allreduce(&nblocal,&natoms,1,MPI_LMP_BIGINT,MPI_SUM,world);
-  if (natoms != atom->natoms) {
+  if (natoms != atom->natoms && comm->me == 0) {
     char str[128];
     sprintf(str,"Lost atoms via change_box: original " BIGINT_FORMAT 
 	    " current " BIGINT_FORMAT,atom->natoms,natoms);
diff --git a/src/change_box.h b/src/change_box.h
index ea5ae8993a0463ba5bee987e08a3269d66643ed9..10c3810aa49eac24acea25e59386283061d97ca6 100644
--- a/src/change_box.h
+++ b/src/change_box.h
@@ -61,7 +61,7 @@ class ChangeBox : protected Pointers {
 
 E: Change_box command before simulation box is defined
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Illegal ... command
 
@@ -71,91 +71,59 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Cannot change_box after reading restart file with per-atom info
 
-UNDOCUMENTED
+This is because the restart file info cannot be migrated with the
+atoms.  You can get around this by performing a 0-timestep run which
+will assign the restart file info to actual atoms.
 
 E: Could not find change_box group ID
 
-UNDOCUMENTED
+Group ID used in the change_box command does not exist.
 
 E: Cannot change_box in z dimension for 2d simulation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Change_box volume used incorrectly
 
-UNDOCUMENTED
+The "dim volume" option must be used immediately following one or two
+settings for "dim1 ..." (and optionally "dim2 ...") and must be for a
+different dimension, i.e. dim != dim1 and dim != dim2.
 
 E: Cannot change_box in xz or yz for 2d simulation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Use of change_box with undefined lattice
 
-UNDOCUMENTED
+Must use lattice command with displace_box command if units option is
+set to lattice.
 
 E: Cannot change box tilt factors for orthogonal box
 
-UNDOCUMENTED
+Cannot use tilt factors unless the simulation box is non-orthogonal.
 
-E: Cannot run 2d simulation with nonperiodic Z dimension
+E: Cannot change box z boundary to nonperiodic for a 2d simulation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot change box to orthogonal when tilt is non-zero
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot change box ortho/triclinic with dumps defined
 
-UNDOCUMENTED
+This is because some dumps store the shape of the box.  You need to
+use undump to discard the dump, change the box, then redefine a new
+dump.
 
 E: Cannot change box ortho/triclinic with certain fixes defined
 
-UNDOCUMENTED
+This is because those fixes store the shape of the box.  You need to
+use unfix to discard the fix, change the box, then redefine a new
+fix.
 
 W: Lost atoms via change_box: original %ld current %ld
 
-UNDOCUMENTED
-
-U: Displace_box command before simulation box is defined
-
-Self-explanatory.
-
-U: Cannot displace_box after reading restart file with per-atom info
-
-This is because the restart file info cannot be migrated with the
-atoms.  You can get around this by performing a 0-timestep run which
-will assign the restart file info to actual atoms.
-
-U: Could not find displace_box group ID
-
-Group ID used in the displace_box command does not exist.
-
-U: Displace_box tilt factors require triclinic box
-
-Cannot use tilt factors unless the simulation box is
-non-orthogonal.
-
-U: Cannot displace_box on a non-periodic boundary
-
-Self-explanatory.
-
-U: Use of displace_box with undefined lattice
-
-Must use lattice command with displace_box command if units option is
-set to lattice.
-
-U: Fix deform volume setting is invalid
-
-Cannot use volume style unless other dimensions are being controlled.
-
-U: Induced tilt by displace_box is too large
-
-The final tilt value must be between -1/2 and 1/2 of the perpendicular
-box length.
-
-U: Lost atoms via displace_box: original %ld current %ld
-
-UNDOCUMENTED
+The command options you have used caused atoms to be lost.
 
 */
diff --git a/src/comm.h b/src/comm.h
index 82ba6a063f3834d2a8c7cdbabbf270adabdbeb12..a285e80ef5b68b14c2773fbf3b3b21a8efba650e 100644
--- a/src/comm.h
+++ b/src/comm.h
@@ -157,30 +157,33 @@ Specified cutoff must be >= 0.0.
 
 E: Specified processors != physical processors
 
-UNDOCUMENTED
+The 3d grid of processors defined by the processors command does not
+match the number of processors LAMMPS is being run on.
 
 E: Cannot use processors part command without using partitions
 
-UNDOCUMENTED
+See the command-line -partition switch.
 
 E: Invalid partitions in processors part command
 
-UNDOCUMENTED
+Valid partitions are numbered 1 to N and the sender and receiver
+cannot be the same partition.
 
 E: Sending partition in processors part command is already a sender
 
-UNDOCUMENTED
+Cannot specify a partition to be a sender twice.
 
 E: Receiving partition in processors part command is already a receiver
 
-UNDOCUMENTED
+Cannot specify a partition to be a receiver twice.
 
 E: Processors grid numa and map style are incompatible
 
-UNDOCUMENTED
+Using numa for gstyle in the processors command requires using
+cart for the map option.
 
 E: Processors part option and grid style are incompatible
 
-UNDOCUMENTED
+Cannot use gstyle numa or custom with the part option.
 
 */
diff --git a/src/compute_erotate_sphere.h b/src/compute_erotate_sphere.h
index ffb5c683df6c1977c9ce3195e4a2d6ea6eccf6ea..d325cd0a7cb99ef2fed01de739739ed85438f269 100644
--- a/src/compute_erotate_sphere.h
+++ b/src/compute_erotate_sphere.h
@@ -50,6 +50,6 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Compute erotate/sphere requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.  
 
 */
diff --git a/src/compute_pair_local.cpp b/src/compute_pair_local.cpp
index af1c415e793aea0c8dd802a191c430becd28f061..a33232db1b4291d54bb0b5d659b0515f3155cdb2 100644
--- a/src/compute_pair_local.cpp
+++ b/src/compute_pair_local.cpp
@@ -96,7 +96,7 @@ void ComputePairLocal::init()
 
   for (int i = 0; i < nvalues; i++)
     if (pstyle[i] == PN && pindex[i] >= force->pair->single_extra)
-      error->all(FLERR,"Pair style does not have single field"
+      error->all(FLERR,"Pair style does not have extra field"
 		 " requested by compute pair/local");
 
   // need an occasional half neighbor list
diff --git a/src/compute_pair_local.h b/src/compute_pair_local.h
index bf399002d79283c4d775287582f11b6277da6bfd..d9ed87d9470fa2634845dd4de15846fb3dc07bd1 100644
--- a/src/compute_pair_local.h
+++ b/src/compute_pair_local.h
@@ -75,10 +75,11 @@ Self-explanatory.
 E: Pair style does not support compute pair/local
 
 The pair style does not have a single() function, so it can
-not be invoked by fix bond/swap.
+not be invoked by compute pair/local.
 
-E: Pair style does not have single field requested by compute pair/local
+E: Pair style does not have extra field requested by compute pair/local
 
-UNDOCUMENTED
+The pair style does not support the pN value requested by the compute
+pair/local command.
 
 */
diff --git a/src/compute_reduce.h b/src/compute_reduce.h
index 6fcded7e3897997b7fbb9fffc9b275a3e9f0525c..90621ac2839b6686da41c0a6d7cac8f8305d2018 100644
--- a/src/compute_reduce.h
+++ b/src/compute_reduce.h
@@ -96,7 +96,7 @@ Self-explanatory.
 
 E: Compute reduce compute array is accessed out-of-range
 
-Self-explanatory.
+An index for the array is out of bounds.
 
 E: Compute reduce compute does not calculate a local vector
 
@@ -124,7 +124,7 @@ Self-explanatory.
 
 E: Compute reduce fix array is accessed out-of-range
 
-Self-explanatory.
+An index for the array is out of bounds.
 
 E: Compute reduce fix does not calculate a local vector
 
@@ -148,7 +148,7 @@ Self-explanatory.
 
 E: Fix used in compute reduce not computed at compatible time
 
-Fixes generate their values on specific timesteps.  Compute sum is
+Fixes generate their values on specific timesteps.  Compute reduce is
 requesting a value on a non-allowed timestep.
 
 */
diff --git a/src/compute_reduce_region.h b/src/compute_reduce_region.h
index d57a20d05aa61da07664801d2470400519d2a132..d27c9f4f811cdb6016ade2d691bd28596a01c5f5 100644
--- a/src/compute_reduce_region.h
+++ b/src/compute_reduce_region.h
@@ -43,7 +43,7 @@ class ComputeReduceRegion : public ComputeReduce {
 
 E: Fix used in compute reduce not computed at compatible time
 
-Fixes generate their values on specific timesteps.  Compute sum is
+Fixes generate their values on specific timesteps.  Compute reduce is
 requesting a value on a non-allowed timestep.
 
 */
diff --git a/src/compute_slice.h b/src/compute_slice.h
index 3acd5c966231ab6df22a4117f5de1b4fc1c1952d..e837fa945b28ae415e62572bd7e0272fd34329dc 100644
--- a/src/compute_slice.h
+++ b/src/compute_slice.h
@@ -56,54 +56,55 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Compute ID for compute slice does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute slice compute does not calculate a global array
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute slice compute vector is accessed out-of-range
 
-UNDOCUMENTED
+The index for the vector is out of bounds.
 
 E: Compute slice compute does not calculate a global vector
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute slice compute array is accessed out-of-range
 
-UNDOCUMENTED
+An index for the array is out of bounds.
 
 E: Compute slice compute does not calculate global vector or array
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix ID for compute slice does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute slice fix does not calculate a global array
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute slice fix vector is accessed out-of-range
 
-UNDOCUMENTED
+The index for the vector is out of bounds.
 
 E: Compute slice fix does not calculate a global vector
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Compute slice fix array is accessed out-of-range
 
-UNDOCUMENTED
+An index for the array is out of bounds.
 
 E: Compute slice fix does not calculate global vector or array
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix used in compute slice not computed at compatible time
 
-UNDOCUMENTED
+Fixes generate their values on specific timesteps.  Compute slice is
+requesting a value on a non-allowed timestep.
 
 */
diff --git a/src/compute_temp_sphere.h b/src/compute_temp_sphere.h
index 118e61ee794119fb51c4dcff61f05ec757cb8a8e..47241bd29a0d7ea6214a8ec19d46d5e28a5427f4 100644
--- a/src/compute_temp_sphere.h
+++ b/src/compute_temp_sphere.h
@@ -60,7 +60,7 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Compute temp/sphere requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Could not find compute ID for temperature bias
 
diff --git a/src/displace_atoms.cpp b/src/displace_atoms.cpp
index 1793a5e195441f3f659713c4274e64228424277a..a46547078b236fae6a2ae8e9c07d597e1f3f5893 100644
--- a/src/displace_atoms.cpp
+++ b/src/displace_atoms.cpp
@@ -211,11 +211,11 @@ void DisplaceAtoms::command(int narg, char **arg)
   bigint natoms;
   bigint nblocal = atom->nlocal;
   MPI_Allreduce(&nblocal,&natoms,1,MPI_LMP_BIGINT,MPI_SUM,world);
-  if (natoms != atom->natoms) {
+  if (natoms != atom->natoms && comm->me == 0) {
     char str[128];
     sprintf(str,"Lost atoms via displace_atoms: original " BIGINT_FORMAT 
 	    " current " BIGINT_FORMAT,atom->natoms,natoms);
-    error->all(FLERR,str);
+    error->warning(FLERR,str);
   }
 }
 
diff --git a/src/displace_atoms.h b/src/displace_atoms.h
index be5921e6191743ad11921605ef7e001c262f4993..cd4601021840e974605fbba98b2e1d47abaca634 100644
--- a/src/displace_atoms.h
+++ b/src/displace_atoms.h
@@ -67,8 +67,8 @@ E: Use of displace_atoms with undefined lattice
 Must use lattice command with displace_atoms command if units option
 is set to lattice.
 
-E: Lost atoms via displace_atoms: original %ld current %ld
+W: Lost atoms via displace_atoms: original %ld current %ld
 
-UNDOCUMENTED
+The command options you have used caused atoms to be lost.
 
 */
diff --git a/src/domain.h b/src/domain.h
index 6a34a334560520cccf906ce5ad8adce7dd511bb7..bf33b6ca5cfe0a5741a5e7180d28ae1dbd4de542 100644
--- a/src/domain.h
+++ b/src/domain.h
@@ -170,9 +170,4 @@ E: Both sides of boundary must be periodic
 Cannot specify a boundary as periodic only on the lo or hi side.  Must
 be periodic on both sides.
 
-U: Triclinic box must be periodic in skewed dimensions
-
-This is a requirement for using a non-orthogonal box.  E.g. to set a
-non-zero xy tilt, both x and y must be periodic dimensions.
-
 */
diff --git a/src/dump_cfg.h b/src/dump_cfg.h
index 0f3c35e33b7f3cd7c595fe227faf32c664a37e7e..576448a695f82b43e3ffe4a48d672f756cd9f3a3 100755
--- a/src/dump_cfg.h
+++ b/src/dump_cfg.h
@@ -50,11 +50,11 @@ class DumpCFG : public DumpCustom {
 
 E: Dump cfg arguments must start with 'id type xs ys zs' or 'id type xsu ysu zsu'
 
-This is a requirement of the CFG output format. :dd
+This is a requirement of the CFG output format.
 
 E: Dump cfg arguments can not mix xs|ys|zs with xsu|ysu|zsu
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid keyword in dump cfg command
 
diff --git a/src/dump_image.h b/src/dump_image.h
index 23d122a0ff620a26c43561104dff4d30acb0e56c..fe9ad7f13c16f59c401d6805dc59292344a99a58 100644
--- a/src/dump_image.h
+++ b/src/dump_image.h
@@ -81,11 +81,12 @@ class DumpImage : public DumpCustom {
 
 E: Invalid dump image filename
 
-UNDOCUMENTED
+The file produced by dump image cannot be binary and must
+be for a single processor.
 
 E: Cannot dump JPG file
 
-UNDOCUMENTED
+LAMMPS was not built with the -DLAMMPS_JPEG switch in the Makefile.
 
 E: Illegal ... command
 
@@ -95,102 +96,88 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Dump image bond not allowed with no bond types
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid dump image theta value
 
-UNDOCUMENTED
+Theta must be between 0.0 and 180.0 inclusive.
 
 E: Dump image persp option is not yet supported
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Dump image requires one snapshot per file
 
-UNDOCUMENTED
+Use a "*" in the filename.
 
 E: Dump image cannot perform sorting
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable name for dump image theta does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable for dump image theta is invalid style
 
-UNDOCUMENTED
+Must be an equal-style variable.
 
 E: Variable name for dump image phi does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable for dump image phi is invalid style
 
-UNDOCUMENTED
+Must be an equal-style variable.
 
 E: Variable name for dump image center does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable for dump image center is invalid style
 
-UNDOCUMENTED
+Must be an equal-style variable.
 
 E: Variable name for dump image zoom does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable for dump image zoom is invalid style
 
-UNDOCUMENTED
+Must be an equal-style variable.
 
 E: Variable name for dump image persp does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable for dump image persp is invalid style
 
-UNDOCUMENTED
+Must be an equal-style variable.
 
 E: Invalid dump image element name
 
-UNDOCUMENTED
+The specified element name was not in the standard list of elements.
+See the dump_modify doc page.
 
 E: Invalid dump image zoom value
 
-UNDOCUMENTED
+Zoom value must be > 0.0.
 
 E: Invalid dump image persp value
 
-UNDOCUMENTED
+Persp value must be >= 0.0.
 
 E: Invalid color in dump_modify command
 
-UNDOCUMENTED
+The specified color name was not in the list of recognized colors.
+See the dump_modify doc page.
 
 E: Dump modify bcolor not allowed with no bond types
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Dump modify bdiam not allowed with no bond types
 
-UNDOCUMENTED
-
-U: Invalid dump image up vector
-
-UNDOCUMENTED
-
-U: Invalid dump image color range
-
-UNDOCUMENTED
-
-U: Illega dump_modify command
-
-UNDOCUMENTED
-
-U: Invalid color map in dump_modify command
-
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/fix_ave_correlate.h b/src/fix_ave_correlate.h
index 72c9e0f852ccc171e439c65beba2b691bcdb9143..cae02b83e46726259e69ecafe50ee51d27b93cd6 100644
--- a/src/fix_ave_correlate.h
+++ b/src/fix_ave_correlate.h
@@ -86,15 +86,15 @@ Self-explanatory.
 
 E: Fix ave/correlate compute does not calculate a scalar
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix ave/correlate compute does not calculate a vector
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix ave/correlate compute vector is accessed out-of-range
 
-UNDOCUMENTED
+The index for the vector is out of bounds.
 
 E: Fix ID for fix ave/correlate does not exist
 
@@ -102,15 +102,15 @@ Self-explanatory.
 
 E: Fix ave/correlate fix does not calculate a scalar
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix ave/correlate fix does not calculate a vector
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix ave/correlate fix vector is accessed out-of-range
 
-UNDOCUMENTED
+The index for the vector is out of bounds.
 
 E: Fix for fix ave/correlate not computed at compatible time
 
@@ -123,6 +123,6 @@ Self-explanatory.
 
 E: Fix ave/correlate variable is not equal-style variable
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/fix_ave_time.h b/src/fix_ave_time.h
index d6f0f4935da213364430a8ea5fb3aa46a2e5d4a6..0423bee3e292c83002727ea4cd2bd9899b1bc17e 100644
--- a/src/fix_ave_time.h
+++ b/src/fix_ave_time.h
@@ -94,13 +94,11 @@ Self-explantory.
 
 E: Fix ave/time compute does not calculate a scalar
 
-Only computes that calculate a scalar or vector quantity (not a
-per-atom quantity) can be used with fix ave/time.
+Self-explantory.
 
 E: Fix ave/time compute does not calculate a vector
 
-Only computes that calculate a scalar or vector quantity (not a
-per-atom quantity) can be used with fix ave/time.
+Self-explantory.
 
 E: Fix ave/time compute vector is accessed out-of-range
 
@@ -112,15 +110,15 @@ Self-explanatory.
 
 E: Fix ave/time compute array is accessed out-of-range
 
-Self-explanatory.
+An index for the array is out of bounds.
 
 E: Fix ave/time fix does not calculate a scalar
 
-A fix used by fix ave/time must generate global values.
+Self-explanatory.
 
 E: Fix ave/time fix does not calculate a vector
 
-A fix used by fix ave/time must generate global values.
+Self-explanatory.
 
 E: Fix ave/time fix vector is accessed out-of-range
 
@@ -137,7 +135,7 @@ Self-explanatory.
 
 E: Fix ave/time fix array is accessed out-of-range
 
-Self-explanatory.
+An index for the array is out of bounds.
 
 E: Variable name for fix ave/time does not exist
 
@@ -145,7 +143,7 @@ Self-explanatory.
 
 E: Fix ave/time variable is not equal-style variable
 
-A variable used by fix ave/time must generate a global value.
+Self-explanatory.
 
 E: Fix ave/time cannot use variable with vector mode
 
diff --git a/src/fix_deform.h b/src/fix_deform.h
index 0fe59ef890ef97c448b97ace53cbd3cc5f81fe0c..7e5b7acb06bf80a04199873b659d66339d0c8f89 100644
--- a/src/fix_deform.h
+++ b/src/fix_deform.h
@@ -88,11 +88,13 @@ is a triclinic (non-orthogonal) box.
 
 E: Cannot use fix deform on a shrink-wrapped boundary
 
-UNDOCUMENTED
+The x, y, z options cannot be applied to shrink-wrapped
+dimensions.
 
 E: Cannot use fix deform tilt on a shrink-wrapped 2nd dim
 
-UNDOCUMENTED
+This is because the shrink-wrapping will change the value
+of the strain implied by the tilt factor.
 
 E: Use of fix deform with undefined lattice
 
@@ -108,11 +110,11 @@ Only one fix deform can be defined at a time.
 
 E: Variable name for fix deform does not exist
 
-UNDOCUMENTED
+Self-explantory.
 
 E: Variable for fix deform is invalid style
 
-UNDOCUMENTED
+The variable must be an equal-style variable.
 
 E: Final box dimension due to fix deform is < 0.0
 
@@ -124,25 +126,12 @@ The trate style alters the current strain.
 
 E: Fix deform cannot use yz variable with xy
 
-UNDOCUMENTED
+The yz setting cannot be a variable if xy deformation is also
+specified.  This is because LAMMPS cannot determine if the yz setting
+will induce a box flip which would be invalid if xy is also changing.
 
 E: Fix deform is changing yz too much with xy
 
-UNDOCUMENTED
-
-U: Cannot use fix deform on a non-periodic boundary
-
-When specifying a change is a box dimension, the dimension must be
-periodic.
-
-U: Cannot use fix deform on a 2nd non-periodic boundary
-
-When specifying a tilt factor change, the 2nd of the two dimensions
-must be periodic.  E.g. if the xy tilt is specified, then the y
-dimension must be periodic.
-
-U: Fix deform is changing yz by too much with changing xy
-
 When both yz and xy are changing, it induces changes in xz if the
 box must flip from one tilt extreme to another.  Thus it is not
 allowed for yz to grow so much that a flip is induced.
diff --git a/src/fix_evaporate.h b/src/fix_evaporate.h
index 11d4b9bf1abe8391fd5c7dc541302e6027f84b2f..065e92d7020f124e210271794b3be11bca0519f1 100644
--- a/src/fix_evaporate.h
+++ b/src/fix_evaporate.h
@@ -70,7 +70,8 @@ a list to enable the atom_modify first command.
 
 W: Fix evaporate may delete atom with non-zero molecule ID
 
-UNDOCUMENTED
+This is probably an error, since you should not delete only one atom
+of a molecule.
 
 E: Fix evaporate molecule requires atom attribute molecule
 
diff --git a/src/fix_langevin.cpp b/src/fix_langevin.cpp
index 60d18a5106170569a6e9447b6f787e1660c850b0..5d910be4626ab7005371ef6c60ee250d2240fc6a 100644
--- a/src/fix_langevin.cpp
+++ b/src/fix_langevin.cpp
@@ -183,9 +183,9 @@ int FixLangevin::setmask()
 void FixLangevin::init()
 {
   if (oflag && !atom->sphere_flag)
-    error->all(FLERR,"Fix langevin omega require atom style sphere");
+    error->all(FLERR,"Fix langevin omega requires atom style sphere");
   if (aflag && !atom->ellipsoid_flag)
-    error->all(FLERR,"Fix langevin angmom require atom style ellipsoid");
+    error->all(FLERR,"Fix langevin angmom requires atom style ellipsoid");
 
   // check variable
 
diff --git a/src/fix_langevin.h b/src/fix_langevin.h
index ab078512a92f9f57214602b548a2cb5a3a46885e..3f4edecc67d44b3bda3441de5a9085c3a914764a 100644
--- a/src/fix_langevin.h
+++ b/src/fix_langevin.h
@@ -86,39 +86,36 @@ The time window for temperature relaxation must be > 0
 
 E: Fix langevin angmom requires atom style ellipsoid
 
-UNDOCUMENTED
+Self-explanatory.
 
-E: Fix langevin omega require atom style sphere
+E: Fix langevin omega requires atom style sphere
 
-UNDOCUMENTED
-
-E: Fix langevin angmom require atom style ellipsoid
-
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable name for fix langevin does not exist
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Variable for fix langevin is invalid style
 
-UNDOCUMENTED
+It must be an equal-style variable.
 
 E: Fix langevin omega requires extended particles
 
-UNDOCUMENTED
+One of the particles has radius 0.0.
 
 E: Fix langevin angmom requires extended particles
 
-UNDOCUMENTED
+This fix option cannot be used with point paritlces.
 
 E: Fix langevin variable returned negative temperature
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot zero Langevin force of 0 atoms
 
-UNDOCUMENTED
+The group has zero atoms, so you cannot request its force
+be zeroed.
 
 E: Could not find fix_modify temperature ID
 
diff --git a/src/fix_nh.cpp b/src/fix_nh.cpp
index 403d17f6889ee6db584467e83b76816d3d5a1bb3..0eb550592870f28e1b3ad666cb7c9dbf5a40923a 100644
--- a/src/fix_nh.cpp
+++ b/src/fix_nh.cpp
@@ -344,7 +344,7 @@ FixNH::FixNH(LAMMPS *lmp, int narg, char **arg) : Fix(lmp, narg, arg)
 	       "with xy dynamics when y is non-periodic dimension");
 
   if (p_flag[3] && scaleyz == 1)
-    error->all(FLERR,"Cannot use fix nvt/npt/nph with"
+    error->all(FLERR,"Cannot use fix nvt/npt/nph with "
 	       "both yz dynamics and yz scaling");
   if (p_flag[4] && scalexz == 1)
     error->all(FLERR,"Cannot use fix nvt/npt/nph with "
@@ -1093,8 +1093,7 @@ void FixNH::remap()
   domain->xz = h[4];
   domain->xy = h[5];
 
-  // tilt factor to cell length ratio can not exceed TILTMAX
-  // in one step
+  // tilt factor to cell length ratio can not exceed TILTMAX in one step
 
   if (domain->yz < -TILTMAX*domain->yprd || domain->yz > TILTMAX*domain->yprd ||
       domain->xz < -TILTMAX*domain->xprd || domain->xz > TILTMAX*domain->xprd ||
diff --git a/src/fix_nh.h b/src/fix_nh.h
index 9d0d773528ad6517c35f96900da92418db83d017..357eff11cb513a1dc9ce88e0f9da4b6959865ec1 100644
--- a/src/fix_nh.h
+++ b/src/fix_nh.h
@@ -46,7 +46,6 @@ class FixNH : public Fix {
   double vol0;                      // reference volume
   double t0;                        // reference temperature 
                                     // used for barostat mass
-
   double t_start,t_stop;
   double t_current,t_target,ke_target;
   double t_freq;
@@ -168,27 +167,27 @@ then the y dimension must be periodic.
 
 E: Cannot use fix nvt/npt/nph with yz dynamics when z is non-periodic dimension
 
-UNDOCUMENTED
+The 2nd dimension in the barostatted tilt factor must be periodic.
 
 E: Cannot use fix nvt/npt/nph with xz dynamics when z is non-periodic dimension
 
-UNDOCUMENTED
+The 2nd dimension in the barostatted tilt factor must be periodic.
 
 E: Cannot use fix nvt/npt/nph with xy dynamics when y is non-periodic dimension
 
-UNDOCUMENTED
+The 2nd dimension in the barostatted tilt factor must be periodic.
 
-E: Cannot use fix nvt/npt/nph withboth yz dynamics and yz scaling
+E: Cannot use fix nvt/npt/nph with both yz dynamics and yz scaling
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot use fix nvt/npt/nph with both xz dynamics and xz scaling
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot use fix nvt/npt/nph with both xy dynamics and xy scaling
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Can not specify Pxy/Pxz/Pyz in fix nvt/npt/nph with non-triclinic box
 
@@ -217,7 +216,8 @@ Self-explanatory.
 
 E: Fix npt/nph has tilted box too far in one step - periodic cell is too far from equilibrium state
 
-UNDOCUMENTED
+Self-explanatory.  The change in the box tilt is too extreme
+on a short timescale.
 
 E: Could not find fix_modify temperature ID
 
diff --git a/src/fix_nh_sphere.h b/src/fix_nh_sphere.h
index 925726c7ebfcefb45531b2beb60677a4a5395735..ed360a23c87c94a7c0a94cba24b5e0d39330a97f 100644
--- a/src/fix_nh_sphere.h
+++ b/src/fix_nh_sphere.h
@@ -37,7 +37,7 @@ class FixNHSphere : public FixNH {
 
 E: Fix nvt/nph/npt sphere requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nvt/sphere requires extended particles
 
diff --git a/src/fix_nve_sphere.h b/src/fix_nve_sphere.h
index 89ffe806e0154e249262b1cbfb0d0be44656fd0c..4fbb0bfcced225c434e5c88d80b3caac33a3834b 100644
--- a/src/fix_nve_sphere.h
+++ b/src/fix_nve_sphere.h
@@ -51,7 +51,7 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Fix nve/sphere requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix nve/sphere requires atom attribute mu
 
diff --git a/src/fix_restrain.cpp b/src/fix_restrain.cpp
index 723f156282df3c4b153151efe908dc7d9489f116..8c5f2d4990bc01393341e4ce8adbbdec8aa915a3 100644
--- a/src/fix_restrain.cpp
+++ b/src/fix_restrain.cpp
@@ -87,9 +87,9 @@ FixRestrain::FixRestrain(LAMMPS *lmp, int narg, char **arg) :
 
   if (rstyle == DIHEDRAL) {
     cos_shift = (double *)
-      memory->smalloc(n_bonds * sizeof(double), "restrain:cos_shift");
+      memory->smalloc(n_bonds * sizeof(double),"restrain:cos_shift");
     sin_shift = (double *)
-      memory->smalloc(n_bonds * sizeof(double), "restrain:sin_shift");
+      memory->smalloc(n_bonds * sizeof(double),"restrain:sin_shift");
     for (ibond = 0; ibond < n_bonds; ibond++) {
       double my_arg = MY_PI * (180.0 + target[ibond]) / 180.0;
       cos_shift[ibond] = cos(my_arg);
diff --git a/src/fix_restrain.h b/src/fix_restrain.h
index 9188b28a5f3175f10df42567b9f275b56ca4c01b..3bf774ffa820d86eb77080427041062292d160d7 100644
--- a/src/fix_restrain.h
+++ b/src/fix_restrain.h
@@ -62,14 +62,17 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Fix restrain requires an atom map, see atom_modify
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Restrain atoms %d %d %d %d missing on proc %d at step %ld
 
-UNDOCUMENTED
+The 4 atoms in a restrain dihedral specified by the fix restrain
+command are not all accessible to a processor.  This probably means an
+atom has moved too far.
 
 W: Restrain problem: %d %ld %d %d %d %d
 
-UNDOCUMENTED
+Conformation of the 4 listed dihedral atoms is extreme; you may want
+to check your simulation geometry.
 
 */
diff --git a/src/fix_rigid.h b/src/fix_rigid.h
index c8fa8f3c60deb50921fb13529eb93e782ecbf490..b69f87e59c4283307963d0948ebf94db6c69df13 100644
--- a/src/fix_rigid.h
+++ b/src/fix_rigid.h
@@ -148,15 +148,15 @@ The fix specification did not end up defining any rigid bodies.
 
 E: Fix rigid z force cannot be on for 2d simulation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix rigid xy torque cannot be on for 2d simulation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix rigid langevin period must be > 0.0
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: One or zero atoms in rigid body
 
diff --git a/src/fix_shake.h b/src/fix_shake.h
index a0727b7cbcb6860a3628c8c6b20106c0d02ed52e..a752357c06aca431bc4986c6631751aadd4a2509 100644
--- a/src/fix_shake.h
+++ b/src/fix_shake.h
@@ -181,19 +181,19 @@ E: Shake atoms %d %d missing on proc %d at step %ld
 
 The 2 atoms in a single shake cluster specified by the fix shake
 command are not all accessible to a processor.  This probably means
-an atom has moved too far. :dd
+an atom has moved too far.
 
 E: Shake atoms %d %d %d missing on proc %d at step %ld
 
 The 3 atoms in a single shake cluster specified by the fix shake
 command are not all accessible to a processor.  This probably means
-an atom has moved too far. :dd
+an atom has moved too far.
 
 E: Shake atoms %d %d %d %d missing on proc %d at step %ld
 
 The 4 atoms in a single shake cluster specified by the fix shake
 command are not all accessible to a processor.  This probably means
-an atom has moved too far. :dd
+an atom has moved too far.
 
 E: Did not find fix shake partner info
 
diff --git a/src/fix_wall_region.h b/src/fix_wall_region.h
index d1cc21a6a11e450570435215c908212fbdf98d15..15a667af6425fc5cd3944051e7996c438b900ac3 100644
--- a/src/fix_wall_region.h
+++ b/src/fix_wall_region.h
@@ -79,11 +79,11 @@ Self-explanatory.
 
 E: Fix wall/region colloid requires atom style sphere
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix wall/region colloid requires extended particles
 
-Self-explanatory.
+One of the particles has radius 0.0.
 
 E: Particle on or inside surface of region used in fix wall/region
 
diff --git a/src/force.h b/src/force.h
index efdca6d1e9e7b02c547eb475f87dc21cb9407e34..c3f1a31c066f437cf422cdd0bc7a80f689d16fd7 100644
--- a/src/force.h
+++ b/src/force.h
@@ -135,7 +135,9 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Numeric index is out of bounds
 
-UNDOCUMENTED
+A command with an argument that specifies an integer or range of
+integers is using a value that is less than 1 or greater than the
+maximum allowed limit.
 
 E: Expected floating point parameter in input script or data file
 
diff --git a/src/image.h b/src/image.h
index 7116294e1b1e156a766f33fa5847d22908408199..3474fcee9e9bed56cac736c67505fd2dea1a3fac 100644
--- a/src/image.h
+++ b/src/image.h
@@ -156,10 +156,10 @@ class Image : protected Pointers {
 
 E: Invalid image up vector
 
-UNDOCUMENTED
+Up vector cannot be (0,0,0).
 
 E: Invalid image color range
 
-UNDOCUMENTED
+The lo value in the range is larger than the hi value.
 
 */
diff --git a/src/input.h b/src/input.h
index 5ecca5a9c4ad9d53375d42ebf8d5b1e8264b0199..e3bf57384db62bb725f100ebb6582a880dd88879 100644
--- a/src/input.h
+++ b/src/input.h
@@ -279,11 +279,13 @@ after a read_data, read_restart, or create_box command.
 
 E: Package command after simulation box is defined
 
-UNDOCUMENTED
+The package command cannot be used afer a read_data, read_restart, or
+create_box command.
 
 E: Package cuda command without USER-CUDA installed
 
-UNDOCUMENTED
+The USER-CUDA package must be installed via "make yes-user-cuda"
+before LAMMPS is built.
 
 E: Pair_coeff command before simulation box is defined
 
diff --git a/src/lammps.h b/src/lammps.h
index 7a6b74d01dc1cea8b528c7169c6984f8b95e97ba..cfc00edb4bcd28f4a31049ae46b7c1660b79b5e4 100644
--- a/src/lammps.h
+++ b/src/lammps.h
@@ -69,7 +69,7 @@ the command you are using to launch LAMMPS.
 
 E: Cannot use -reorder after -partition
 
-UNDOCUMENTED
+Self-explanatory.  See doc page discussion of command-line switches.
 
 E: Processor partitions are inconsistent
 
@@ -83,11 +83,11 @@ The -in command-line option must be used to specify a file.
 
 E: Can only use -pscreen with multiple partitions
 
-UNDOCUMENTED
+Self-explanatory.  See doc page discussion of command-line switches.
 
 E: Can only use -plog with multiple partitions
 
-UNDOCUMENTED
+Self-explanatory.  See doc page discussion of command-line switches.
 
 E: Cannot open universe screen file
 
@@ -143,14 +143,15 @@ The size of the MPI datatype does not match the size of a bigint.
 
 E: Small, tag, big integers are not sized correctly
 
-UNDOCUMENTED
+See description of these 3 data types in src/lmptype.h.
 
 E: 64-bit atom IDs are not yet supported
 
-UNDOCUMENTED
+See description of this data type in src/lmptype.h.
 
 E: Cannot use -cuda on without USER-CUDA installed
 
-UNDOCUMENTED
+The USER-CUDA package must be installed via "make yes-user-cuda"
+before LAMMPS is built.
 
 */
diff --git a/src/memory.h b/src/memory.h
index 681af216ab0b1623783342ee0ecf32f4c028020b..aa1ec6e1972534f1d8bda40660a4abc04b51f00a 100644
--- a/src/memory.h
+++ b/src/memory.h
@@ -552,12 +552,12 @@ class Memory : protected Pointers {
 E: Failed to allocate %ld bytes for array %s
 
 Your LAMMPS simulation has run out of memory.  You need to run a
-smaller simulation or on more processors. :dd
+smaller simulation or on more processors.
 
 E: Failed to reallocate %ld bytes for array %s
 
 Your LAMMPS simulation has run out of memory.  You need to run a
-smaller simulation or on more processors. :dd
+smaller simulation or on more processors.
 
 E: Cannot create/grow a vector/array of pointers for %s
 
diff --git a/src/neigh_bond.h b/src/neigh_bond.h
index c698aad115f3c8f84ed3211991f98aafd20ecc93..a79fa16ef37ee9bafcf8b207b7c2b19f89dcaf1d 100644
--- a/src/neigh_bond.h
+++ b/src/neigh_bond.h
@@ -18,27 +18,27 @@ E: Bond atoms %d %d missing on proc %d at step %ld
 One or both of 2 atoms needed to compute a particular bond are
 missing on this processor.  Typically this is because the pairwise
 cutoff is set too short or the bond has blown apart and an atom is
-too far away. :dd
+too far away.
 
 E: Angle atoms %d %d %d missing on proc %d at step %ld
 
 One or more of 3 atoms needed to compute a particular angle are
 missing on this processor.  Typically this is because the pairwise
 cutoff is set too short or the angle has blown apart and an atom is
-too far away. :dd
+too far away.
 
 E: Dihedral atoms %d %d %d %d missing on proc %d at step %ld
 
 One or more of 4 atoms needed to compute a particular dihedral are
 missing on this processor.  Typically this is because the pairwise
 cutoff is set too short or the dihedral has blown apart and an atom is
-too far away. :dd
+too far away.
 
 E: Improper atoms %d %d %d %d missing on proc %d at step %ld
 
 One or more of 4 atoms needed to compute a particular improper are
 missing on this processor.  Typically this is because the pairwise
 cutoff is set too short or the improper has blown apart and an atom is
-too far away. :dd
+too far away.
 
 */
diff --git a/src/neigh_derive.h b/src/neigh_derive.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_derive.h
+++ b/src/neigh_derive.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neigh_full.h b/src/neigh_full.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_full.h
+++ b/src/neigh_full.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neigh_gran.h b/src/neigh_gran.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_gran.h
+++ b/src/neigh_gran.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neigh_half_bin.h b/src/neigh_half_bin.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_half_bin.h
+++ b/src/neigh_half_bin.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neigh_half_multi.h b/src/neigh_half_multi.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_half_multi.h
+++ b/src/neigh_half_multi.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neigh_half_nsq.h b/src/neigh_half_nsq.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_half_nsq.h
+++ b/src/neigh_half_nsq.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neigh_respa.h b/src/neigh_respa.h
index 06d220eb40857a5d4aaa827ce6edb4e9c053d4c0..2b9b9d420ce50142864964bbc1d8582eba7e3fee 100644
--- a/src/neigh_respa.h
+++ b/src/neigh_respa.h
@@ -15,12 +15,8 @@
 
 E: Neighbor list overflow, boost neigh_modify one
 
-UNDOCUMENTED
-
-U: Neighbor list overflow, boost neigh_modify one or page
-
 There are too many neighbors of a single atom.  Use the neigh_modify
-command to increase the neighbor page size and the max number of
-neighbors allowed for one atom.
+command to increase the max number of neighbors allowed for one atom.
+You may also want to boost the page size.
 
 */
diff --git a/src/neighbor.h b/src/neighbor.h
index 8e7177bb01373a8f0976b1b55c92533f0c3464e9..36d80fb7e2ac52f33208ddf18bcafdcd4722531a 100644
--- a/src/neighbor.h
+++ b/src/neighbor.h
@@ -338,7 +338,9 @@ This is a current restriction within LAMMPS.
 
 E: Too many local+ghost atoms for neighbor list
 
-UNDOCUMENTED
+The number of nlocal + nghost atoms on a processor
+is limited by the size of a 32-bit integer with 2 bits
+removed for masking 1-2, 1-3, 1-4 neighbors.
 
 W: Building an occasional neighobr list when atoms may have moved too far
 
diff --git a/src/pair_beck.h b/src/pair_beck.h
index 989b1a996e07809a32fd282f0f242700059bb4c1..4fcc99501a8ed94b7d5bfc87c0e574ff849de629 100644
--- a/src/pair_beck.h
+++ b/src/pair_beck.h
@@ -56,14 +56,17 @@ class PairBeck : public Pair {
 
 E: Illegal ... command
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script syntax and compare to the
+documentation for the command.  You can use -echo screen as a
+command-line option when running LAMMPS to see the offending line.
 
 E: Incorrect args for pair coefficients
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script or data file.
 
 E: All pair coeffs are not set
 
-UNDOCUMENTED
+All pair coefficients must be set in the data file or by the
+pair_coeff command before running a simulation.
 
 */
diff --git a/src/pair_born_coul_wolf.cpp b/src/pair_born_coul_wolf.cpp
index 0b33eb75496582c13ff3e8ded68fa85808476a81..db4a8849107c6d7287e8f1b3657198270fba20e3 100644
--- a/src/pair_born_coul_wolf.cpp
+++ b/src/pair_born_coul_wolf.cpp
@@ -279,7 +279,7 @@ void PairBornCoulWolf::coeff(int narg, char **arg)
 void PairBornCoulWolf::init_style()
 {
   if (!atom->q_flag)
-    error->all(FLERR,"Pair style born/coul/Wolf requires atom attribute q");
+    error->all(FLERR,"Pair style born/coul/wolf requires atom attribute q");
 
   int irequest = neighbor->request(this);
 
diff --git a/src/pair_born_coul_wolf.h b/src/pair_born_coul_wolf.h
index 0792682a2a7177b863ac552dc2b4160a13bf29f0..1042e68800707e2282549b1243a86c1450ead3a6 100644
--- a/src/pair_born_coul_wolf.h
+++ b/src/pair_born_coul_wolf.h
@@ -66,9 +66,9 @@ E: Incorrect args for pair coefficients
 
 Self-explanatory.  Check the input script or data file.
 
-E: Pair style born/coul/Wolf requires atom attribute q
+E: Pair style born/coul/wolf requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 E: All pair coeffs are not set
 
diff --git a/src/pair_coul_wolf.h b/src/pair_coul_wolf.h
index f4b6f37759028fc71789a0541c0e0aa98397170c..d73602ca872bbbe97750cce53974b1b8cd6023dd 100644
--- a/src/pair_coul_wolf.h
+++ b/src/pair_coul_wolf.h
@@ -64,6 +64,6 @@ Self-explanatory.  Check the input script or data file.
 
 E: Pair coul/wolf requires atom attribute q
 
-UNDOCUMENTED
+The atom style defined does not have this attribute.
 
 */
diff --git a/src/pair_dpd.h b/src/pair_dpd.h
index b74c0aaf8f18f202f640265ce0ae3bd99abe6785..9ee8ead873db036215a2d5fceba671109ed2d25b 100644
--- a/src/pair_dpd.h
+++ b/src/pair_dpd.h
@@ -73,7 +73,7 @@ Use the communicate vel yes command to enable this.
 
 W: Pair dpd needs newton pair on for momentum conservation
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: All pair coeffs are not set
 
diff --git a/src/pair_hybrid.h b/src/pair_hybrid.h
index ad1356ec606f66a070c0b62823eb80b791a09833..61a717e5dbdd106440fe70d6c929a460c0f30927 100644
--- a/src/pair_hybrid.h
+++ b/src/pair_hybrid.h
@@ -121,9 +121,4 @@ E: Coulomb cutoffs of pair hybrid sub-styles do not match
 If using a Kspace solver, all Coulomb cutoffs of long pair styles must
 be the same.
 
-U: Pair style hybrid cannot use same pair style twice
-
-The sub-style arguments of pair_style hybrid cannot be duplicated.
-Check the input script.
-
 */
diff --git a/src/pair_lj_smooth_linear.h b/src/pair_lj_smooth_linear.h
index c45ca10d771259611907eff66668edbf87b97ef7..43d9238a7711249138d059b4d8cd1ada7cbec29d 100644
--- a/src/pair_lj_smooth_linear.h
+++ b/src/pair_lj_smooth_linear.h
@@ -57,10 +57,12 @@ class PairLJSmoothLinear : public Pair {
 
 E: Illegal ... command
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script syntax and compare to the
+documentation for the command.  You can use -echo screen as a
+command-line option when running LAMMPS to see the offending line.
 
 E: Incorrect args for pair coefficients
 
-UNDOCUMENTED
+Self-explanatory.  Check the input script or data file.
 
 */
diff --git a/src/procmap.cpp b/src/procmap.cpp
index 18e740673c7b9760acf948a5b2d846c4675c1ed3..e7abb8e4dad5117e40db23678ba41097efc0b215 100644
--- a/src/procmap.cpp
+++ b/src/procmap.cpp
@@ -182,7 +182,7 @@ void ProcMap::numa_grid(int nprocs, int *user_procgrid, int *procgrid,
       user_procgrid[0] > 1 ||          // user specified grid > 1 in any dim
       user_procgrid[1] > 1 ||
       user_procgrid[2] > 1)
-    error->all(FLERR,"Could not create numa 3d grid of processors");
+    error->all(FLERR,"Could not create numa grid of processors");
   
   // user settings for the factorization per numa node
   // currently not user settable
@@ -336,7 +336,7 @@ void ProcMap::custom_grid(char *cfile, int nprocs,
       if (cmap[i][3] <= 0 || cmap[i][3] > procgrid[2]) flag = 1;
     }
   }
-  if (flag) error->all(FLERR,"Processors custom grid file is invalid");
+  if (flag) error->all(FLERR,"Processors custom grid file is inconsistent");
 }
 
 /* ----------------------------------------------------------------------
@@ -653,7 +653,7 @@ void ProcMap::output(char *file, int *procgrid, int ***grid2proc)
   FILE *fp;
   if (me == 0) {
     fp = fopen(file,"w");
-    if (fp == NULL) error->one(FLERR,"Cannot open processors custom file");
+    if (fp == NULL) error->one(FLERR,"Cannot open processors output file");
     fprintf(fp,"LAMMPS mapping of processors to 3d grid\n");
     fprintf(fp,"partition = %d\n",universe->iworld+1);
     fprintf(fp,"Px Py Pz = %d %d %d\n",procgrid[0],procgrid[1],procgrid[2]);
diff --git a/src/procmap.h b/src/procmap.h
index 1a4159e09ad240e56210009a5e95dbeac1170553..d8376040dfd067dabd39594b0ae8e153859347c2 100644
--- a/src/procmap.h
+++ b/src/procmap.h
@@ -60,42 +60,41 @@ class ProcMap : protected Pointers {
 
 E: Could not create 3d grid of processors
 
-UNDOCUMENTED
+The specified constraints did not allow a Px by Py by Pz grid to be
+created where Px * Py * Pz = P = total number of processors.
 
 E: Processors twogrid requires proc count be a multiple of core count
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Could not create twolevel 3d grid of processors
 
-UNDOCUMENTED
-
-E: Could not create numa 3d grid of processors
-
-UNDOCUMENTED
+The specified constraints did not allow this style of grid to be
+created.
 
 E: Could not create numa grid of processors
 
-UNDOCUMENTED
+The specified constraints did not allow this style of grid to be
+created.  Usually this is because the total processor count is not a
+multiple of the cores/node or the user specified processor count is >
+1 in one of the dimensions.
 
 E: Cannot open custom file
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Unexpected end of custom file
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Processors custom grid file is inconsistent
 
-UNDOCUMENTED
-
-E: Processors custom grid file is invalid
-
-UNDOCUMENTED
+The vales in the custom file are not consistent with the number of
+processors you are running on or the Px,Py,Pz settings of the
+processors command.  Or there was not a setting for every processor.
 
-E: Cannot open processors custom file
+E: Cannot open processors output file
 
-UNDOCUMENTED
+Self-explanatory.
 
 */
diff --git a/src/read_data.h b/src/read_data.h
index 9ef79f706081c6aee31064c2bd7e68e819cd75d0..cc5d413468e7578b404416fd8e48df466366675f 100644
--- a/src/read_data.h
+++ b/src/read_data.h
@@ -100,27 +100,28 @@ section.
 
 E: Invalid data file section: Ellipsoids
 
-UNDOCUMENTED
+Atom style does not allow ellipsoids.
 
 E: Must read Atoms before Ellipsoids
 
-UNDOCUMENTED
+The Atoms section of a data file must come before a Ellipsoids
+section.
 
 E: Invalid data file section: Lines
 
-UNDOCUMENTED
+Atom style does not allow lines.
 
 E: Must read Atoms before Lines
 
-UNDOCUMENTED
+The Atoms section of a data file must come before a Lines section.
 
 E: Invalid data file section: Triangles
 
-UNDOCUMENTED
+Atom style does not allow triangles.
 
 E: Must read Atoms before Triangles
 
-UNDOCUMENTED
+The Atoms section of a data file must come before a Triangles section.
 
 E: Invalid data file section: Bonds
 
@@ -284,15 +285,15 @@ section.  Something is wrong with the format of the data file.
 
 E: No ellipsoids allowed with this atom style
 
-UNDOCUMENTED
+Self-explanatory.  Check data file.
 
 E: No lines allowed with this atom style
 
-UNDOCUMENTED
+Self-explanatory.  Check data file.
 
 E: No triangles allowed with this atom style
 
-UNDOCUMENTED
+Self-explanatory.  Check data file.
 
 E: System in data file is too big
 
@@ -375,7 +376,8 @@ dihedrals or impropers would be included, but they were not present.
 
 E: Needed bonus data not in data file
 
-UNDOCUMENTED
+Some atom styles require bonus data.  See the read_data doc page for
+details.
 
 E: Cannot open gzipped file
 
diff --git a/src/run.h b/src/run.h
index 48224f3eccd3dc728d442c285c9dcc646480f38b..8d2b8ad0ebe729c561136fbac9fed0a2773fbde0 100644
--- a/src/run.h
+++ b/src/run.h
@@ -71,6 +71,6 @@ Self-explanatory.
 
 E: Too many timesteps
 
-UNDOCUMENTED
+The cummulative timesteps must fit in a 64-bit integer.
 
 */
diff --git a/src/set.h b/src/set.h
index 73b9e58834888b03d444be920d103f1365290605..b1951b452312a5baf7d595258558b0b4191d78e6 100644
--- a/src/set.h
+++ b/src/set.h
@@ -79,23 +79,23 @@ The attribute being set does not exist for the defined atom style.
 
 E: Invalid mass in set command
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid shape in set command
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid length in set command
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid dipole length in set command
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid diameter in set command
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot set non-zero image flag for non-periodic dimension
 
@@ -103,7 +103,7 @@ Self-explanatory.
 
 E: Cannot set meso_rho for this atom style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot use set atom with no atom IDs defined
 
@@ -111,7 +111,7 @@ Atom IDs are not defined, so they cannot be used to identify an atom.
 
 E: Cannot use set mol with no molecule IDs defined
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Could not find set group ID
 
@@ -123,11 +123,11 @@ Region ID specified in set command does not exist.
 
 E: Cannot set quaternion for atom that has none
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot set theta for atom that is not a line
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Bond atom missing in set command
 
diff --git a/src/thermo.h b/src/thermo.h
index c1a07ab0bf45f2d6149a08f657f1f09c96330e53..ceac5be9cb1a7bb0c15ab6484416f0378fd232a8 100644
--- a/src/thermo.h
+++ b/src/thermo.h
@@ -209,7 +209,7 @@ does not match these timesteps.
 
 E: Could not find thermo variable name
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Too many total atoms
 
@@ -217,7 +217,19 @@ See the setting for bigint in the src/lmptype.h file.
 
 E: Lost atoms: original %ld current %ld
 
-UNDOCUMENTED
+Lost atoms are checked for each time thermo output is done.  See the
+thermo_modify lost command for options.  Lost atoms usually indicate
+bad dynamics, e.g. atoms have been blown far out of the simulation
+box, or moved futher than one processor's sub-domain away before
+reneighboring.
+
+W: Lost atoms: original %ld current %ld
+
+Lost atoms are checked for each time thermo output is done.  See the
+thermo_modify lost command for options.  Lost atoms usually indicate
+bad dynamics, e.g. atoms have been blown far out of the simulation
+box, or moved futher than one processor's sub-domain away before
+reneighboring.
 
 E: Thermo style does not use temp
 
diff --git a/src/universe.cpp b/src/universe.cpp
index b473c9c794a62d9e283e26b634d2f8471ad8a8ba..b9d88ca70060ac6f2e4a798deeeafde38026d685 100644
--- a/src/universe.cpp
+++ b/src/universe.cpp
@@ -112,16 +112,16 @@ void Universe::reorder(char *style, char *arg)
       sscanf(line,"%d %d",&me_orig,&me_new);
       if (me_orig < 0 || me_orig >= nprocs ||
 	  me_new < 0 || me_new >= nprocs)
-	error->one(FLERR,"Invalid entry in reorder file");
+	error->one(FLERR,"Invalid entry in -reorder file");
       uni2orig[me_new] = me_orig;
 
       for (int i = 1; i < nprocs; i++) {
 	if (!fgets(line,MAXLINE,fp))
-	  error->one(FLERR,"Unexpected end of reorder file");
+	  error->one(FLERR,"Unexpected end of -reorder file");
 	sscanf(line,"%d %d",&me_orig,&me_new);
 	if (me_orig < 0 || me_orig >= nprocs ||
 	    me_new < 0 || me_new >= nprocs)
-	  error->one(FLERR,"Invalid entry in reorder file");
+	  error->one(FLERR,"Invalid entry in -reorder file");
 	uni2orig[me_new] = me_orig;
       }
       fclose(fp);
diff --git a/src/universe.h b/src/universe.h
index fafca73834fe03f4260ae936820b286e65eaa06c..7d831d0b0bfe075cf950024fe61de86f46ce2337 100644
--- a/src/universe.h
+++ b/src/universe.h
@@ -54,27 +54,23 @@ class Universe : protected Pointers {
 
 E: Invalid -reorder N value
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Nprocs not a multiple of N for -reorder
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot open -reorder file
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Unexpected end of -reorder file
 
-UNDOCUMENTED
+Self-explanatory.
 
-E: Invalid entry in reorder file
+E: Invalid entry in -reorder file
 
-UNDOCUMENTED
-
-E: Unexpected end of reorder file
-
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid command-line argument
 
diff --git a/src/update.h b/src/update.h
index 12f947269ef5b8a4cce3760b70ed4ee65428d63c..36b27f22a6427dd289d19c3fd83e8a9eb0f49ba0 100644
--- a/src/update.h
+++ b/src/update.h
@@ -66,11 +66,11 @@ class Update : protected Pointers {
 
 E: USER-CUDA mode requires CUDA variant of run style
 
-UNDOCUMENTED
+CUDA mode is enabled, so the run style must include a cuda suffix.
 
 E: USER-CUDA mode requires CUDA variant of min style
 
-UNDOCUMENTED
+CUDA mode is enabled, so the min style must include a cuda suffix.
 
 E: Illegal ... command
 
@@ -80,7 +80,7 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Illegal integrate style
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Cannot reset timestep with dump file already written to
 
@@ -106,10 +106,10 @@ are defined.
 
 E: Timestep must be >= 0
 
-Specified timestep size is invalid.
+Specified timestep is invalid.
 
 E: Too big a timestep
 
-UNDOCUMENTED
+Specified timestep is too large.
 
 */