University of Oregon

Perform a Fresh Install of Mac OS X 10.5 or 10.6


Although Mac OS 10.5 and 10.6 both offer an archive install feature, which allows you to keep your personal files in tact (See Reinstall OS X and Keep Your Personal Files), sometimes a fresh install of Mac OS X is required.

It's a good idea to do this if you are selling your computer or want to securely remove data on your hard drive.

1. Either while the computer is on, or immediately on startup, insert the Mac OS X disk into the computer.

2. Boot up the computer. Immediately after hearing the Macintosh startup chime on the grey screen, press and hold the "C" key.

3. Choose your preferred language

4. Go to the Utilities menu at the top and select Disk Utility.

5. Choose the hard drive, and click the "Erase" tab. Choose Mac OS Extended as the file type and choose a name for your freshly formatted hard drive.

Note: It is possible to recover data from a hard drive erased in the standard format. If you require a more secure method of formatting, click the security options button and choose an appropriate level of data destruction.

6. Click Erase.

7. Now you can quit the Disk Utility which will take you back to the Mac OS X Installer. Choose the Hard Drive from this window and click Install.

8. This process will take about a half an hour or more depending on the speed of your Mac.

9. When the process is completed, click Restart and you will have a completely blank version of Mac OS X!