You might like to run the System File Checker to check if any system files are corrupted.

Open System Information (Start Menu > Programs > Accessories > System Tools). Then click on Tools | System File Checker.

If it doesn't work try reinstalling. You don't have to format your drive to do this; just run Setup.exe on the root of the Win CD and let it do its thing.

Daniel Irvine
F-Free - Free Stuff and Freebies!