CCleaner (Crap Cleaner) is a System Optimization tool that removes unused and temporary files allowing Windows to run faster, more efficiently, and gives you more hard disk space. I use CCleaner at least once a week to cleanup the temporary files and cookies on my PC. You can also use CCleaner to clean up your computer’s registry.
The only tool I use on a regular basis to clean my PC’s registry is CCleaner. As far as I know it’s never screwed up my PC because it’s a very mild and safe Registry Cleaner. Once you have installed CCleaner click on the Registry button on the left side the click Scan For Issues at the bottom. It will then scan and list all the issues it found. CCleaner won’t delete or change any registry entries until you click the Fix Issues button in the lower right corner. Before it fixes the registry issues CCleaner will prompt you to backup your registry which is recommended.
I think you’ll find CCleaner does a pretty good job of finding old entries. You might want to run it 2-3 times in a row until it doesn’t find anything to fix.