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Erasing Your Personal Data Before You Sell or Trash Your Hard Drive
People throw out all kinds of things in the trash that can be used to collect information about them and potentially steal their identity. Bank statements, utility bills, magazines, pre-approved credit card solicitations and even other junk mail all contain clues about you.
Many people use some sort of paper shredder to turn all of these kinds of documents into confetti before throwing them out. They want to make sure that nobody can pick up their trash and gain information about them. When it comes to disposing of your computer system, or a hard drive from your computer system, you need to be just as diligent.
Computers continue to become obsolete within a year or two, maybe three, and many people upgrade their existing computers or buy an entirely new one. The old computer or equipment can often be difficult to dispose of because nobody else wants obsolete equipment either.
But, whether you give your computer equipment away, sell it on eBay or just set it at the curb with the rest of your trash, you need to take appropriate precautions to ensure your personal and confidential data does not get passed on.
A study by Simson Garfinkel, author of Database Nation, found that drives purchased on eBay routinely contain sensitive or confidential data. Garfinkel was able to purchase an old ATM machine hard drive on eBay that contained 827 unique account PIN numbers. He purchased another drive on eBay that had previously been owned by a medical center. That drive contained information on 31,000 credit card numbers.
Whether you are planning to sell your drive or computer on eBay, or just throw it away, you need to make sure the data on the drive is impossible to recover. Frankly, data is almost always recoverable to some degree, but with the proper precautions you can at least make sure that Joe Shmoe that bought your hard drive from your garage sale can't access your Quicken financial information.
First, you should understand that deleting files, and even formatting your hard drive, are not sufficient. Both processes really just remove the information the hard drive needs to find the data, not the data itself. Deleted files can be undeleted and formatted hard drives can be recovered.
To be sure that your data is removed beyond all practical ability to recover it, you should use a wiping or erasing utility. These tools overwrite every sector of the hard drive with binary 1's and 0's. Those that meet government security standards even overwrite each sector multiple times for added protection.
Check out the tools below and be sure to adequately wipe or erase your hard drive before you get rid of the drive itself or your whole computer with the drive still in it.
* CyberCide
* WipeDrive
* DataEraser