A couple of things you could try.
- Firstly, run a Check Disk operation to check and fixing any potential corrupt system file errors:- 'Start'>'All Programs'>'Accessories' then RIGHT-Click on 'Command Prompt' and select 'Run as Administrator'
- In The 'Administrator: Command Prompt' window type "CHKDSK /F" then press the enter key and in response to the "Y/N" question press and enter "Y"
- Restart your computer and the Chkdsk program will auto start on boot-up, let it run until it completes and restarts your computer.
- Second thing to try, in addition to the Chkdsk is again open a command prompt window as as Administrator and enter the command "SFC /SCANNOW" which Scans verify the versions of all protected system files and replaces any that are missing or corrupt.
There is a third option in that you check through the Windows System and Application logs files for any logged errors that may help determine the cause of the problem: 'Start'>'Control Panel'>'System and Security'>'Administrative Tools'>'Event Viewer'
Hope that helps.