-Using the System File Checker (SFC):
If you are experiencing system lockups or error messages when using Windows applications, you can try running the System File Checker tool to scan your operating system for corrupt files. If the SFC finds any corrupt files, it will automatically replace them with "known" good files. Here's how to use SFC: Go to Start In the Search field, type in: cmd Right click the "cmd" entry Select "Run as administrator". Continue through any resulting UAC prompts. At the command prompt, type in the following command: sfc /scannow Press Enter on your keyboard