Apple Z0FS0LL User Guide - Page 44

To use Apple Hardware Test on your MacBook Air: 1 Disconnect all external devices from your computer 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. 5 When the Apple Hardware Test main screen appears (after about 45 seconds), follow the onscreen instructions. 6 If Apple Hardware Test detects a problem, it displays an error code. Make a note of the error code before pursuing support options. If Apple Hardware Test doesn't detect a hardware failure, the problem may be software related. If this procedure doesn't work, you can open Apple Hardware Test using Remote Install OS X and the Applications Install DVD. For more information about Apple Hardware Test, see the Apple Hardware Test Read Me file on the Applications Install DVD that came with your computer. Reinstalling Software Using Remote Install Mac OS X Use Remote Install Mac OS X on the partner computer whose optical disc drive you want to share (installation instructions for this and other components of the DVD or CD Sharing Setup software are on page 15) when you want to do one of the following tasks on your MacBook Air:  Reinstall Mac OS X and other software that came with your MacBook Air  Reset your password 44 Chapter 3 Problem, Meet Solution