1. Click the 'Start' menu and then go over to the 'All Programs' button.
2. Go to the 'Accessories' tab and right-click on the 'Command Prompt' option in the menu.

3. Click on the 'Run as administrator' tab and enter your administrator password into the field when prompted.
4. Type 'sfc /scannow' into the command prompt and press the 'Enter' key. The computer will scan your system and replace corrupted files with the correct versions.