To Scan the drive, click Check Now. Check both options, then click Start. An error message will tell you that Windows can't check the disk while it's in use. Click Schedule disk check (Vista or Win7) or Yes (XP). Then, the next time you plan to leave your computer for a few hours (for instance, to sleep), reboot. Windows will take a considerable amount of time (ballpark guestimate: one hour for each 100GB of drive space) before it's ready for regular use.
Twice a Year: Backup your hard drive as an image. While not as important as a recent backup of your data (see Daily), an image backup of your entire drive can be a life-saver should your hard drive crash or Windows become hopelessly corrupt. A good image backup means never having to reinstall Windows from scratch.
For more information, see Strategy 5 in 7 Backup Strategies for Your Data, Multimedia, and System Files.
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