Hi,
Sometimes, some of the windows protected files can be lost or changed. To detect any problems run the program “System File Checker” (SFC). Before you run it you should purge your PC’s cache:-

Go to “START”
Click “RUN”
Type or “copy and paste”.. sfc.exe /purgecache

Note:- the space after “exe”.

The “purgecache” in this command will empty the cache before you run the file checker. You should always purge the cache before scanning with the System File Checker (SFC). That way, you can be sure that system files are copied from your Windows installation media, and are not infected with malware or corrupted. After the cache has been purged, run System File Checker.

Go to “START”
Click “RUN”
Type or “copy and paste”… sfc.exe /scannow

Note:- the space after “exe”. You may be required to use your installation disk.

This could take a long time to complete, when finished, reboot and see if the problem still exists.


Another possibility is that you have a virus or malware, go to the "Viruses, Spyware and other Nasties" site here and read about how to remove them.