CCleaner
1. Download Piriform's CCleaner to your hard drive. Double-click the executable to launch the installer. Follow the onscreen prompts to install CCleaner.
2. Launch the software from the 'All Programs' tab on the 'Start' menu. Select the 'Registry' tab. Click 'Scan for issues.' CCleaner will search your registry for any errors.

3. Select 'Fix Selected Issues' when the status bar reaches 100 percent. Click 'Yes' to create a registry backup. Save the registry backup to the 'My Documents' folder on your computer, or, ideally, to a USB flash drive.
4. Click 'Fix All Selected Issues.' Click 'OK.' Click 'Close.' Exit out of Piriform CCleaner.
Eusing Free Registry
5. Download and install Eusing Free Registry Cleaner. Click 'Skip' at the start-up window, or enter your registry key, if applicable.
6. Click 'File' from the menu. Click 'Backup.' Choose a location to save the registry file to and click 'Save.'
7. Select 'Scan registry issue' from the sidebar. Click 'Repair registry issue.' Click 'Close' when the prompt appears. Exit out of Eusing Free Registry Cleaner when you have finished repairing all issues.
TweakNow RegCleaner
8. Download and install TweakNow RegCleaner. Click 'Start,' 'All Programs,' then 'TweakNow RegCleaner' to launch the application.
9. Uncheck 'Clean traces of your computer.' Select 'Analyze' from the 'Window Cleaner' tab.
10. Click 'Fix and Clean' to repair any errors RegCleaner has detected.