To do a proper disk check, you will need it to automatically fix file system errors and do a deeper scan. To do this:
1.Go into (My) Computer
2.Right-click the drive with the problem
3.Choose Properties.
4.Click the Tools tab (at the top of the box that appears)
5.Click Check Now.
6.Tick Both boxes at the top, then click Start.
7. Windows will ask if you want to schedule the disk check on next system restart: Click Yes/Schedule Disk Check
8.Restart the computer - the disk check will take place during the restart.
This applies to XP,Vista and Windows 7.
Shane