AssKickr is a little application that was developed to launch .exe files. It is also distributed unzipped, so that it will run immedately.

So, if you ever associate .exe files with a program, don't panic. You don't have to format your hard drive, you just need AssKickr to help you launch RegEdit and get rid of the association (hence AssKickr).

Just replace the program that lauches every time you start an .exe file (the one you associated .exe files with) with AssKickr (this can even be done in DOS). AssKickr will then launch any file in its command line, effectively restoring Windows functionality back to normal. Don't forget to delete the association afterwards!