Have you ever said here which version of Mach4 you're running? Are you running Mach4 stone stock other than motion controller plugin and ports/pins for your setup or do you have a bunch of screen edits to customize? If pretty stock, even if NOT, you can rename C:/Mach4hobby to something like C/Mach4hobby_OLD and reinstall, then copy stuff in Screens, Plugins, Licenses, Profiles, Modules, over to the new install. But........if you or someone else has written some bad script in the screenset, they're going to come along!!
Again, if you go to the Offsets tab and click Tool Table and Fixture Table, there's nothing in there you don't expect?