Windows comes with many utilities and settings that you can use to keep your system running at top performance. In this lesson, you'll learn about some of them, and you'll have a chance to try them on your own computer.

Check a Drive for Errors

Disks can sometimes develop errors in the way the files are stored, and those errors can affect system performance. Disk errors sometimes manifest themselves in odd ways -- everything from missing files to out-of-memory errors.

The primary cause of these errors is abnormal or improper shutdown -- in other words, shutting off the computer's power or restarting the system while a program is in use. unexpected shutdowns aren't always your fault, of course; sometimes a power outage occurs or Microsoft Windows locks up.

There are two types of errors a disk can have: physical and logical. A physical error is a bad spot on the disk, usually caused by physical trauma such as dropping the computer while it's running. A logical error, which is much more common, is an error in the table of contents of the disk's storage system. The Check Disk utility in Windows XP can fix both types.

If you're having problems with your computer, it's a good idea to run Check Disk to make sure a disk error is not the root of the problem. You might also run Check Disk every month or so as routine preventive maintenance.

To check a disk for errors, open the My Computer window. Right-click the hard disk (or one of them, if you have multiple) and select Properties. On the Tools tab, click Check Now to open the Check Disk dialog box, shown in Figure 5-1.

Figure 5-1: Check Disk Main (C:) dialog box.

There are two options available:

• Automatically fix file system errors: If you mark this, Check Disk fixes any problems it finds rather than prompt you about each one. Beginners should mark this; advanced users who are curious about what errors are found should not.
• Scan for and attempt recovery of bad sectors: If you mark this, Check Disk does both a logical and a physical test. Because each physical test takes a long time (an hour or more in some cases) and because physical errors are less common, most people use this option only occasionally (once every few months or so) or only if a disk read or write error has occurred.

Click Start to begin the check. If you didn't mark the Automatically fix file system errors checkbox, and if any errors are discovered during the check, a dialog box appears asking whether you want to fix them. Click Yes to fix each error.

If you see a message that the disk can't be checked now because it requires exclusive access, click Yes to schedule a start the next time you start your computer. Then restart (Start > Shut Down > Restart).