Help improve your PC's performance with Check Disk

Is your PC running a little more slowly than usual? If you've run a full-service Windows Live OneCare safety scan and still think your PC is too sluggish, it's possible your computer's hard disk drive has one or more disk errors. Fortunately, there's a free Windows utility you can use to fix this—and it's available right from the Start menu.

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What does it mean?

sector
A portion of the data storage area on a hard disk.

What are disk errors?

Your PC's hard disk, through normal everyday use, can develop bad sectors, lost clusters, and directory errors. These force your computer to work harder to locate or save files, which might be what's making your PC seem slower than usual.

How do I fix disk errors?

Windows comes with a free built-in utility called Check Disk. This program will scan your hard disk, locate errors, and ask if you'd like to fix them.

Before you run Check Disk, we strongly recommend backing up any important files you keep on your PC. If there's indeed a bad sector or other corruption on your hard disk, Check Disk might not be able to recover certain files as it attempts to fix the problem. Learn more about backing up your files.

You can run Check Disk directly from the Start menu:

1. Click Start, click My Computer, and then right-click the local disk you want to check (usually, this is drive C).

2. Click Properties, and then click Tools.

3. Under Error-checking, click Check Now.... Make sure both check boxes are selected, then click Start.

4. Because Check Disk needs exclusive access to some Windows files, it will display a dialog box asking you whether you'd like to run Check Disk the next time you restart your PC. Click Yes.

5. Click Start, then Shut Down.

6. From the dropdown menu, select Restart, then click OK. Once your PC restarts, Check Disk will begin running.

What will happen when I run Check Disk?

The first thing to note about Check Disk is that it will take at least an hour—and likely longer—to run through its routine. And since you won't be able to use any other programs while Check Disk is running, you should run it when you don't need to use your computer for a while.

Once you've restarted your PC according to the directions above, you won't see your desktop and all the program icons you're accustomed to seeing when you start up your computer. Instead, you'll see a blue screen as Check Disk begins checking your hard disk. It goes through five separate stages, allowing you to monitor its progress as it works. After it finishes all its tasks, it will automatically restart your computer, and you'll be able to use it again as you did before.

How often should I run Check Disk?

If you use your PC daily, we recommend running Check Disk weekly. You can do this automatically with Windows Scheduler:

1. On the Start menu, click Control Panel.

2. In Control Panel in Classic View, double-click Scheduled Tasks.

3. Double-click Add Scheduled Task. The Scheduled Task Wizard appears. Click Next.

4. Check Disk isn't available within the scroll-down list. You'll need to select it manually. Click Browse. Then navigate to windows\system32\chkdsk.exe. Select chkdsk.exe and click Open.

5. The Scheduled Task Wizard prompts you to define the frequency for chkdsk.exe to run. Select Weekly and click Next.

6. You're then asked to select the time and day you want this task to start. Select a time you won't likely be using your computer. Make sure this start time differs from any other tasks you've scheduled.

7. Enter your user name and password (the one you use when you need to log on to your computer). Click Next.

8. A wizard page appears, telling you you've successfully scheduled Check Disk to run and confirming the start time. Click Finish to have Windows automate this task.