The pages on this site contain documentation for very old MS-DOS software,
purely for historical purposes.
If you're looking for up-to-date documentation, particularly for programming,
you should not rely on the information found here, as it will be woefully
out of date.
SYS1591
SYS1591Explanation
A VER or CHA command was found in the patch instruction file without a
previous FILE command specifying the file to patch.
Action
Check the patch instruction file for errors or contact the supplier of the
patch instruction file.