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You may also use the Windows XP Setup disks. If using the disks you will have to install each disk when prompted during the setup. This will start the Windows XP setup program. This prompt will appear shortly after the (POST) power-on self test. Once the CD loads, press the Enter key at the Welcome to Setup screen. Since there is already an existing Windows XP installation you may receive a prompt to repair it. Press the ESC key to bypass this option and continue formatting the disk. " All your existing partitioned and non-partitioned spaces will be listed on the screen. Use the arrow keys to select fields to be deleted. When prompted, press the L key to confirm partition deletion. This will clear old data from the hard drive of the computer. " Now that all the partitioned spaces are deleted, press the C key to create a new partitioned space. Press enter to create a new partition of the maximum size.

Summary:
Insert the Windows XP CD-ROM or DVD-ROM into your computer. Restart the PC. Press any key to boot from CD when prompted. Press the F8 key to agree to the Microsoft end user license agreement when prompted to do so. Select each field that does not say "Unallocated Space. Press the D key to delete each field. Repeat steps 6 and 7 until the only field left is "Unallocated Space.