Have you tried this:-
Click Start, next All Programs, Accessories, System Tools, and then System Restore.
Select Restore my computer to an earlier time and click Next.
On the calendar that is displayed, a date in bold font indicates that a restore point was created that day. Select a date on which, or prior to, you know your system was working correctly, and click Next.
You will receive a confirmation window. Click Next to start the restore process. The system will automatically restart as part of the process.