This was originally posted by andro11meda in Hardware and Networking Support. It worked so well for me on a problem-computer that I was working on that I had to post it in tutorials. Thanks andro11meda!!
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This is my favorite way to wipe it clean:
CAUTION: This debug script is for advanced users only. Its Purpose is to remove all formatting and partitioning information from your hard disk when FDISK is unable to do so. THIS WILL REMOVE ALL DATA AND PROGRAMS FORM THE DRIVE.
1. Create a MSDOS bood disk with Debug