System errors can occur if hard disks contain damaged sectors or fragmented files. Repair and defragment hard disks, either by using the Error-checking tool and Disk Defragmenter utility included with Windows or by using a third-party disk utility (for example, Symantec Norton Utilities). You should run such utilities on each hard disk or partition. More information about the Error-checking tool and Disk Defragmenter appears below; for more information about a third-party disk utility, refer to the documentation for the utility.
The Error-checking tool repairs bad sectors, lost allocation units and file fragments, cross-linked files, and invalid file names. To access the Error-checking tool, choose Start > My Computer, right-click the desired hard disk, and choose Properties from the menu. In the Local Disk Properties dialog box, click the Tools tab, and then click Check Now in the Error-checking area.
Note: To prevent Disk Defragmenter from moving files to bad sectors of a disk, run the Error-checking tool before running Disk Defragmenter.
Disk Defragmenter rearranges the files and free space on your computer so that files are stored in contiguous units and free space is consolidated in one contiguous block. To access the Disk Defragmenter utility, choose Start > All Programs > Accessories > System Tools > Disk Defragmenter.