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out of date.
SYS1401
SYS1401Explanation
The TRACE utility detects that there are incorrect major event codes listed
after the ON/OFF parameter.
Action
Retry the command using a correct major event code number between 0 and
255.