Use these steps to restore to the factory settings and the software that originally came with your computer by using the installation DVDs that shipped with it.Important: For MacBook Air, a MacBook Air SuperDrive, or MacBook Air Software Reinstall Drive is required to complete this procedure.This procedure has four parts:

Important: This procedure will completely erase your hard drive. If you have installed Microsoft Windows using Boot Camp, or have multiple partitions, this procedure will erase the partition you select.

Part One: Erasing the hard drive

  1. Turn on the computer.
  2. Insert the Mac OS X Install DVD into the optical drive, or insert the MacBook Air Software Reinstall Drive into the USB port.
  3. Restart the computer.
  4. Press and hold the "C" key while the computer starts up. The computer will start up using the Install media. Alternatively, press and hold the Option key at startup to select the volume containing the installer.
  5. If your are using a wireless mouse, a mouse icon should appear asking you to turn the mouse on so that the computer can discover it.
  6. Select a language, then press the right arrow key.
  7. Click the Utilities menu, the choose Disk Utility.
  8. Select a volume to erase (usually called Macintosh HD).
  9. Click the Erase tab.
  10. Click Erase... Important: This step will completely erase your hard drive. If you have installed Microsoft Windows using Boot Camp, or have multiple partitions, this procedure will erase the partition you select.
  11. A dialog box appears asking if you want to erase the partition: click Erase.
  12. After the partition is erased, choose Quit Disk Utility from the Disk Utility menu.

Part Two: Installing the operating system

  1. When the Mac OS X Snow Leopard Installer screen appears, click Continue.
  2. When the license agreement appears, click Agree.
  3. Select the disk you erased. It should now be highlighted with a green arrow.
  4. Click Install. A status bar appears on the bottom of the screen while Mac OS X installs.
  5. An Additional Information screen appears, advising you that you operating system has been installed. Click Continue.
  6. An Install Succeeded screen appears. Click Restart.

Part Three: Completing the Mac OS X Setup Assistant

  1. When the restart has completed, a welcome video plays, then country/region selection screen appears.
  2. Select your country or region and click Continue.
  3. Select a keyboard layout and click Continue.
  4. A migration screen appears. If you wish to migrate your data from another Macintosh, see Migration tips and tricks. If you do not wish to migrate, or want to migrate later, select "Do not transfer my information now" and click Continue.
  5. A Wireless Service screen appears if you have wireless services available within range of your computer. Select "On" and click Continue.
  6. If the network is password protected, you be asked for a password when you select it. Type the password and click Continue.
  7. An Apple ID screen appears. This is used to purchase content from the iTunes store. When complete, click Continue.
  8. If you do not have an Apple ID, click Continue to move to the next screen.
  9. A Registration Information screen appears. You are not required to fill this out, but it is helpful if you do. When complete, click Continue and your product registration will be sent immediately.
  10. If Mac OS X servers are available on your network, you'll be asked if you'd like to log on to them. If not, click Continue.
  11. A Create Your Account screen appears. This will be used to create a User Account with Login ID and Password for you computer. You should remember this password. You'll be asked for it when you install new software or perform other administrative tasks on your computer. When complete, click Continue and your account will be created immediately.
  12. A screen to select your user picture appears. Take a snapshot with the built-in camera or select a picture from your Library. When complete, click Continue.
  13. A MobileMe screen appears. Select an option and click Continue.
  14. A Thank You screen appears. Click Go to complete the Mac OS X Setup Assistant.
  15. Eject the Mac OS X Install DVD by dragging its icon to the Trash.

Part Four: Installing the bundled applications

  1. To install the bundled applications, locate the Applications Install Disc or MacBook Air Software Reinstall Drive that came with your computer.
    Note: You may see a Software Update icon bouncing up and down in your dock. You can quit this for now.
  2. Insert the Applications Install Disc into the optical drive, or insert the MacBook Air Software Reinstall Drive into the USB port.
  3. The disc will mount and an Applications Install Disk dialog appears. Double-click on Install Bundled Software to install your iLife applications. If you are using the MacBook Air Software Reinstall Drive, double-click the Install iLife icon.
  4. A dialog appears asking if you want to run the package. Click Continue.
  5. The Bundled Software Applications Installer screen appears. Click Continue.
  6. A software license screen appears. Click Continue, then click Agree to accept the terms.
  7. A select destination dialog appears. Make sure the partition with the green arrow is the correct destination, then click Continue.
  8. To install all the bundled applications, click Install.
  9. To select individual applications, click Customize. Click the disclosure triangle next to Bundled Applications to select individual applications, then click Install. Clicking Standard Install on the Customize screen installs all the applications.
  10. Type the password you created in Part Three, step 11 to start the installation.
  11. A restart dialog appears. Click Continue Installation.
  12. An Install was Successful screen appears. Click Restart.

The restore process is now complete.

It is a good idea to make sure you've updated all the software after performing this procedure. From theApple () menu, choose Software Update to find the updates currently available for your computer.