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out of date.
SYS1599
SYS1599Explanation
The file to be appended cannot be opened for reading.
Action
Make sure the file exists and the filename is spelled correctly.