I’ve been using this old tool for years; it has saved my caboose (and users’ machines) more times than I can count. In all this time, I haven’t had one problem with using it. In fact, it is one of the most stable products that Microsoft has ever invented. Of course, they don’t support it - you’re entirely on your own if you choose to use it. (And that’s the CYA disclaimer, folks.)

One of my favorite uses for RegClean is getting rid of a program that fails to uninstall properly. Certain installers put files in places where they can get accidentally, or intentionally, deleted (such as windows/temp) and when you go to uninstall the program, the uninstaller won’t let you. Some applications won’t let you install a new version unless the old version is uninstalled. It’s a Catch-22. RegClean to the rescue!

Manually delete the folder(s) containing the application’s files and reboot. Rebooting will re-initialize the registry and any pointers to the program files that are now missing will be broken. Run RegClean and most of these registry keys will be cleaned out. Voila! Uninstall complete. Now you should be able to install the new version.

Running RegClean on a regular basis will keep your registry relatively free of junk, especially if you install and uninstall lots of programs. And a clean registry means fewer errors.