|Odd. I pulled the defrag files from DOS 6.22 and used them on a DOS 5 machine with no problems (though I'm not doubting there may be an issue). If so, then an older version of Norton Utilities should have a defragmentation tool that should work.|
Nonetheless, if the DOS 3.1 machine is one you use routinely (or plan on using for some while), it may be of some benefit to go ahead an upgrade to a newer version of DOS 6.x, assuming you have access to the disks.
"Channeling the spirit of jboy..."