If Windows 7 develops a problem it can often be fixed by running this utility. The sfc /scannow command (System File Checker) scans the integrity of all protected Windows 7 system files and replaces incorrect corrupted, changed, or damaged versions with the correct versions if possible. It needs to be run from an Elevated Command Prompt. Right click: "Command Prompt" in "Start Menu - Accessories". Click: "Run as Administrator". Click past the UAC Screen. In the Command Prompt Type: sfc /scannow and press "Enter" It might or might not need your Windows Installation Disk in case it needs to fix something. It will let you know if it does. I've seen it go both ways. It'll take a while. If you get a message saying it couldn't fix some files you can find out which ones. When SFC runs, it logs it's actions to the C:\WINDOWS\LOGS\CBS\CBS.LOG. Open the Elevated command prompt again. Type in: findstr /c:"[SR]" %windir%\logs\cbs\cbs.log >%userprofile%\Desktop\sfcdetails.txt and press "Enter". This will place a sfcdetails.txt file on your desktop with the SFC scan details from the CBS.LOG. Open the sfcdetails.txt and look for the unfixable entries. The last time I ran this I found this entry. "2009-08-09 13:16:27, Info CSI 000002db [SR] Unable to complete Verify and Repair transaction because some of the files that need to be repaired are in use. A reboot is required to complete this operation". All I had to do was reboot to fix it. There were others that it was able to fix. I've had great luck running this utility on Windows 7 and Xp in the past. Once we get Service Packs for W7 that will open up another issue but not until then. In order to run this on XP SP3 I had to make a Windows XP SP3 Slipstream Disk. It's not a problem on W7 now though. We'll cross that bridge when we come to it. There's a lot of other info out there on this. You could google for it if you like.