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Clean your Registry can make your computer faster

You will want to perform a repair of Windows to get it working again. This will not lose your settings but it will replace all the system files that Windows has, basically making a fresh install whilst keeping all your personalized details.

To do this, you just need to put the Windows CD into the drive, boot from the CD and then proceed as if you are installing a fresh version of Windows (by pressing enter NOT r). Then when it says to repair the current version of Windows, you just click the button it tells you to and it will do it. This should make it work, otherwise you will need to wipe your system and do a fresh install.

Open computer in safe mode and scan your system with registry cleaner.

Did you ever try to go somewhere in your car without the engine running? You can try to boot windows in safe mode, then maybe run your registry cleaner.