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Disk Utility provides the same basic functionality as Chkdsk does for Windows machines. You will need a Mac OS X installation DVD. Hold down the “C” key. This will load the setup program for Mac OS. Choose your language to continue. You can find it in the desktop menu bar. Select the hard drive you wish to repair and click Repair Volume. If Repair Volume is successful, then you can run Repair Permissions as well.
Launch Disk Utility. Turn on the Mac and insert the CD. Open Disk Utility.