To clean up files on your hard drive, you can defragment using the below steps:
Choose Start→Control Panel→System and Security.The Administrative Tools window appears.
Click Defragment Your Hard Drive. The Disk Defragmenter dialog box appears.
Click the Analyze Disk button. This step checks whether your disk requires defragmenting. A drive with 10 percent or more fragmentation should be defragmented. (If you’ve been using your computer for a while, the drive may show 50 percent fragmentation or more.)
When the analysis is complete, click the Defragment Disk button. A notation displays the progress of defragmenting your drive. When the defragmenting process is complete, the Disk Defragmenter dialog box shows that your drive no longer requires defragmenting.
Click Close. The Disk Defragment dialog box and the Control Panel close.
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