HOW TO ERASE A HARD DRIVE

Overwrite and Reformat is Risky:

• Overwrite is generally effective at covering over portions of the hard drive that can be successfully written over, however, crashed hard drives cannot be overwritten because you cannot run software on an inoperable hard drive.
• All drives contain bad sectors. These sectors cannot be accessed by an overwrite program unless you have the original bit map.
• The read/write heads shift causing tracking errors. The overwrite program will write over information contained in the current track, but fails to write over data contained on previous tracks.
• G-List, or Ghost List, is the auto recovery tool on your hard drive. The G-List will automatically save documents without you knowing it to prevent data loss. Overwrite programs are not able to access the G-List even with the original bit map.
• The BIOS (Basic Input/Output System) will only recognize the hard drive capacity the computer started with. For example, if you start with a 280 gig hard drive and up upgrade to a 320 gig, the computer is only going to recognize the first 280 gig, leaving 40 gig of information untouched by the overwrite program.
• Have to be compatible with the hard drive standard. Overwrite programs either work with IDE or SCSI, but not both, requiring you to purchase more than one program.
• Can be size dependent. If you purchase a program and then upgrade your hard drives, the program may not erase your higher capacity disks.
• Due to their time consuming nature, government audits have shown that many hard drives are not actually overwritten, but rather just signed off on as having been overwritten.
• Even built-in programs, such as “Secure Erase,” fail to write over all portions of a hard drive, leaving information behind.

Furthermore, both government and independent testing has shown that overwrite and formatting software leaves sections of information behind. Ultimately, both groups determined that the only way to remove all information from a hard drive or tape is to degauss with a degausser that has passed testing by the National Security Agency.

When it comes to erasing a hard drive, only one method—DEGAUSSING—can guarantee the complete elimination of data. Let’s take a look at overwrite and reformat software programs first.