There are several reasons to restore a computer back to factory settings: if you want to sell the computer to someone, correct faulty software downloads, or clear the memory. These steps will help you to get back the factory settings without a problem.
Make sure to transfer all of the files you want to keep to a USB memory stick or burn to a CD.
Put the Restore Factory Settings CD into the CD drive. This CD was packaged with your computer.
Confirm you want to restore the factory settings. The computer will begin restoring all settings. Don't disturb your computer, as this process can take several hours. .
Reboot the computer to complete the process.
Turn on your computer. Right away there will be a black screen. You can restore factory settings without a CD, too. This will reset your BIOS.
Press F1 when the black screen appears; you will enter the setup configuration mode. You will be presented with a menu.
Select Restore Factory Defaults. Your computer will do all the work for you. As with the CD, this process may take several hours.
If you do not have the restore CD, contact the manufacturer for a new one.
This process will delete everything but the operating system and factory downloaded software.