diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index e5eec31ebb0b23ef3f8a8a9ebb085a464c8d6eb1..3dc1dac00c76b675a49a2b3b7ffc577a96dce816 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -34,19 +34,19 @@ list(APPEND SRC_AUTOGEN_FILES ${LAMMPS_SOURCE_DIR}/lmpinstalledpkgs.h)
 foreach(_SRC ${SRC_AUTOGEN_FILES})
   get_filename_component(FILENAME "${_SRC}" NAME)
   if(EXISTS ${LAMMPS_SOURCE_DIR}/${FILENAME})
-          message(FATAL_ERROR "\nFound file(s) generated by the make-based build system.\nPlease run 'make -C ${LAMMPS_SOURCE_DIR} purge'")
+          message(FATAL_ERROR "\nFound header file(s) generated by the make-based build system.\nPlease run 'make -C ${LAMMPS_SOURCE_DIR} purge' to remove")
   endif()
 endforeach()
 
-# check for files installed by make-based buildsystem
-# only run this time consuming check if there are new files
+# check for files from packages installed by the make-based buildsystem
+# this is slow, so only run this check if there are new files
 if(NOT SRC_FILES STREQUAL SRC_FILES_CACHED)
   file(GLOB SRC_PKG_FILES ${LAMMPS_SOURCE_DIR}/*/*.cpp)
   message(STATUS "Running check for packages installed with 'make yes-<package>' (this may take a while)")
   foreach(_SRC ${SRC_PKG_FILES})
     get_filename_component(FILENAME "${_SRC}" NAME)
     if(EXISTS ${LAMMPS_SOURCE_DIR}/${FILENAME})
-      message(FATAL_ERROR "\nFound package(s) installed by the make-based build system\nPlease run 'make -C ${LAMMPS_SOURCE_DIR} no-all purge'")
+      message(FATAL_ERROR "\nFound package(s) installed by the make-based build system\nPlease run 'make -C ${LAMMPS_SOURCE_DIR} no-all purge' to uninstall")
     endif()
   endforeach()
   set(SRC_FILES_CACHED "${SRC_FILES}" CACHE INTERNAL "List of file in LAMMPS_SOURCE_DIR" FORCE)