Wise Registry Cleaner offers a fast cleaner to scan for errors on the registry. It has the capability to defragment your computer's registry (which means it will need a restart, so make sure all your applications are closed before running it) and it can also backup your registry if it's not working correctly. This cleaner comes with a few nice features including a "reboot manager" which enables you to automatically restart your PC if the program does fail to complete the scan. It also has a backup facility for you to store on your hard drive so you can restore your computer should anything go wrong.
The only issue I have ever encountered with Wise Registry Cleaner is that it doesn't work for Windows Vista. The reason I say this is because this application is only compatible with Windows XP and Vista. However, since it's such a useful tool, I've installed it on both of my computers and let it run on the default settings. Now it's been over 6 months since I've downloaded this program and I've had no problems at all. The reason I say it's running smoothly on my machine is because I've always used it in conjunction with RegCure. RegCure scans your PC for errors every time you use your computer and then it runs an updated version of the cleaner. Since the software is made to run alongside this program it should automatically detect and remove any errors from your PC.
If you want to try out the software for free, there's a demo version available online. Just visit my website to download the latest free trial version and allow it to scan your PC for free. I've tried other free registry cleaners but they don't compare to Wise Registry Cleaner because it's the best free tool available.