This tool cleans the codecs for specific file, the problem is that it doesen't associate the file with any other codec... so it stops working, until you have reinstaled it.
Preferred Filter Tweaker
Win7DSFilterTweaker helps you configure your preferred DirectShow decoders fast and easy. It is also known as Preferred Filter Tweaker for Windows 7.
BigFix
BigFix is a very helpful kit which helps you solve problems related to audio or video filters and codecs.
Autoplay Repair
If you are dealing with invalid entries left after uninstalling an application, Autoplay Repair can help you solve the problem and remove corrupted entries from Windows XP’s autoplay.
DivX AntiFreeze
DivX AntiFreeze prevents media players from freezing playback when video clips contain invalid frames.