A "Folder From Hell" is a folder which appears to be empty but cannot
be trashed; that is, you can put it in the trash, but you get an error
when you try to empty the trash. The problem persists even though you
have rebooted your Mac and no applications are running which could
possibly be using the folder. (From the documentation)

This utility program repairs the folder's record in the disk's catalog
file with the changes taking effect after a reboot. It may not always
fix the problem and there are [ other less low-level methods][1] you
should probably try first.

Compatibility
Architecture: 68k

  [1]: http://tidbits.com/1992/01/27/system-7-bugs-problems/