Sometimes an unexpected power loss or program error can create inaccessible file segments that take up space on a disk. The Check Disk program that comes with Windows helps you find and repair damaged sections of a disk. Check Disk can also be used to find physical disk errors or bad sectors . The program doesn't physically repair your media, but it moves data away from any bad sectors it finds. To keep your hard disk drive working properly, you should run Check Disk from time to time. When you run Check Disk, all files must be closed for the process to run. While the Check Disk process is running, your hard disk will not be available to perform any other task.
Check a Disk for Errors