How do I repair my hard drive's directory (repair disk)?

We like to repair our hard drives about once a month. This mends any directory damage on the hard drive before small problems can turn into big ones. To do this you'll need the grey system disc that came with your Mac originally or any Mac OS X upgrade disc that you've purchased since. You can also use DiskWarrior (our favorite).

BACK UP FIRST

Although most disk repairs go off without a hitch, you should make sure your data is backed up before doing this. See Get Ahead by Backing Up to get started.

 If your Mac won’t start up normally you can start up your Mac using a system disc or the built-in recovery partition introduced in OS 10.7 Lion.

For OS 10.6 or earlier, you’ll need a system install disc (this is the first gray disc from the set that came with your Mac) or any operating system installation disc you’ve purchased. With the system disc in your computer, restart the Mac while holding down the C key. If holding C doesn’t work, try holding the Option key during startup, which should allow you to select the Mac OS disc icon and press Return. If the disc is immediately ejected, you may have a stuck button on your mouse or trackpad. Turn off the Mac, unplug the mouse, and try again. It will also be ejected if it isn’t really a system disc and is lacking the software needed to start up your computer.

For OS 10.7 or later, your Mac should already have a recovery partition installed. Once your Mac is off, hold down Command-R immediately after you press the power button to access it. If this doesn’t work, try using the instructions above with the gray system install DVD that came with your Mac.

1. Wait for the installer disc or recovery partition to finish loading. We are not going to install the system now; we are starting up this way so we can run Disk Utility.
2. In OS 10.6 and earlier, look under the Utilities menu, and choose Open Disk Utility… In OS 10.7 and later, a Mac OS X Utilities window should appear, select Disk Utility.

WARNING

Don’t click Erase—that will wipe out everything on your drive.

3. If you see your startup disk on the left side of the Disk Utility window, you can try to repair it using Disk Utility. Select your startup volume by name, and then click Repair Disk.
4. When finished, quit Disk Utility. If you’re using OS 10.6 or earlier, look in the Utilities menu, and choose Startup Disk. If you’re using OS 10.7 or later, look in the Apple () menu, and choose Startup Disk. For either system, if you see your disk in the list, select it, and click the Restart button. If you still get a blinking icon, you might need to reinstall your system.

You can also repair disk permissions while you're here but there is no need to do this regularly. Read "What does Repair Disk Permissions do?" for instructions and more information.

Published April 29, 2009 9:49 PM
Last modified on November 25, 2011 11:45 AM