Write an article based on this "Download and install CCleaner from the developer's website. Run CCleaner. Click the "Registry" option in the left menu. Ensure that all of the boxes are checked. Click the "Scan for Issues" button CCleaner will begin scanning your registry, and any errors will be displayed in the right frame. Click the "Fix selected issues" button. Make a backup of the registry when prompted. Click the "Fix All Selected Issues" button. Click "Close" after everything is fixed. Reboot your computer."
CCleaner is a free utility made by Piriform. You can download it from piriform.com/ccleaner/. The free version is sufficient for repairing the registry. When installing CCleaner, most users can leave the settings as they are. This program will scan your registry for errors, and then attempt to fix them for you.  This will make CCleaner scan for as many errors as possible.  By default, all of the problems that are found will be checked. This will help ensure that you can restore your settings if something goes wrong with CCleaner. You can review each fix manually, but you can typically trust CCleaner to make the correct repair.  If the problems persist, you may need to reinstall Windows 7.  You can try to manually fix your registry using the Registry Editor, but this is only recommended for advanced users as one wrong edit can render your computer inoperable until the system is restored or reinstalled.