Apple MacBook Air (11-inch, Mid 2011) - Manual (Page 46)

46 Chapter 3 Problem, Meet Solution
1 Make sure your MacBook Air is connected to the Internet by using an Ethernet or Wi-Fi
network. (To connect to a Wi-Fi network, follow the instructions on page 43.)
2 In the Mac OS X Utilities pane, select Disk Utility and click Continue.
3 Select the disk in the list on the left, and then click the Erase tab.
4 Select Mac OS Extended (Journaled) from the Format pop-up menu, type a name for
the disk, and then click Erase.
5 After the disk is erased, choose Disk Utility > Quit Disk Utility.
6 In the Mac OS X Utilities pane, select Reinstall Mac OS X and click Continue.
7 To reinstall Mac OS X and your applications, follow the instructions in the Mac OS X
Installer.
After restoring Mac OS X and your Apple applications, you can selectively restore your
other data and applications from a Time Machine backup.
Checking for a Hardware Problem
If you suspect a hardware problem, use the Apple Hardware Test application to help
determine if there’s a problem with one of the MacBook Air components, such as the
memory or processor.
To use Apple Hardware Test:
1 Disconnect all external devices from your MacBook Air except the power adapter.
2 Restart your MacBook Air while holding down the D key.
3 When the Apple Hardware Test chooser screen appears, select the language you want
to use.
4 Press the Return key or click the right arrow button.