How to Recover an Optiplex 745by T.M. Wit
To recover your Dell Optiplex 745, you will need the Dell recovery discs that came with your PC. Dell creates recovery discs to help users return their computers to factory condition. You will have to first change your BIOS settings so your Dell Optiplex 745 boots from CD.
Turn on your computer and press "F8" to access your BIOS menu.
Tab over to "Boot Device."
Move your CD-Rom to the top of the list, then press "F11" to exit and save changes.
Insert your Dell recovery disc into your optical drive, then restart your computer.
Press any key to boot from disc.
Select the "Full Recovery" option and click "Next." Allow the recovery disc to return your computer to factory condition.