[. . . ] Note: You don't need to use Remote Install Mac OS X to upgrade Mac OS X on a Mac without an optical drive. However, if you need to restore your Mac to factory settings, then you need to use Remote Install Mac OS X. 1 Make sure both computers are on the same network (wired or wireless). 2 Make sure you have installed DVD or CD Sharing on the computer whose optical drive you're using. [. . . ] Note: You can use Remote Install Mac OS X to restore your computer to factory settings on a Mac without an optical drive, using another computer's optical drive. To use Remote Install Mac OS X, first follow the instructions in "Using Remote Install Mac OS X" later in this document, and then go to step 3 in this section. 3 When the Language Chooser appears, select your language, and then click the Continue button (looks like an arrow). 5 Select your disk from the list on the left, and then click the Erase tab. 6 Select Mac OS Extended (Journaled) from the Format pop-up menu, type a name for your disk, and then click Erase. After the disk has been erased, choose Disk Utility > Quit Disk Utility, and then follow the instructions in the Mac OS X Installer to reinstall Mac OS X. Note: Once the installation is complete, you may be prompted to use the Applications installation disc that came with your computer to reinstall your iLife applications (GarageBand, iPhoto, iMovie, iDVD, and iWeb). To reinstall your iLife applications, insert the Applications installation disc, double-click the Install Bundled Software icon, and then follow the onscreen instructions. 4 Using Remote Install Mac OS X You can use Remote Install Mac OS X to restore your computer to factory settings on a Mac without an optical drive, using another computer's optical drive. The other computer must have Mac OS X 10. 4. 10 or later, or Microsoft Windows XP or Windows Vista. 1 Make sure both computers are on the same network (wired or wireless). Note: You can't use Remote Install Mac OS X with a WEP-protected wireless network. 2 Make sure that you have installed DVD or CD Sharing on the computer whose optical drive you're using. If the computer is a Mac with Mac OS X 10. 5. 3 or later, DVD or CD Sharing is installed.  To install DVD or CD Sharing on a Mac with Mac OS X 10. 4. 10-10. 5. 2, see: http://support. apple. com/downloads/DVD_or_CD_Sharing_Setup_Update_for_Mac  On a Windows computer, see: http://support. apple. com/downloads/DVD_or_CD_ Sharing_Update_1_0_for_Windows 3 Insert the Mac OS X installation disc into the computer's optical drive. 4 On the computer whose optical drive you're using, open Remote Install Mac OS X.  On a Mac, it is located in the Utilities folder in the Applications folder.  On a Windows computer, choose Remote Install Mac OS X from the Install Assistant. 5 Follow the onscreen instructions. Read the introduction, select the installation disc you want to use, and depending on your type of network, select AirPort or Ethernet. 6 On the computer where you're installing the software, hold down the Option key while restarting the computer, until you see the list of available startup disks. 7 On the computer with the installation disc, click Continue in Remote Install Mac OS X. Note: If you selected AirPort as your network in step 5, choose your AirPort network from the pop-up menu. When you see the AirPort status icon indicating signal strength, click Continue in Remote Install Mac OS X. [. . . ] 4 If you were unable to install Mac OS X again, choose Utilities > Disk Utility. Select the disk on which you want to install, click First Aid, and then click Repair Disk. After repairing any problems, quit Disk Utility and then click Continue to try installing again. If you're still unable to install Mac OS X, try erasing the disk before installing Mac OS X. [. . . ]