Okay, so you have upgraded one or more computers in your office (perhaps to go to Vista, you brave soul!) and are wondering what to do with the old ones. You can take them home for the kids to use, donate them to a local charity or school, or sell them at a computer flea market or on EBay. However, before you do that, you need to consider all the sensitive and confidential information that may reside on the hard drive.

You could delete it all or reformat the hard drive, but that is not enough; a determined (and sometimes not-so-determined) future user might still be able to get at the data. This is because simply deleting the files just removes that file’s entry in the disk’s directory; it does not remove the file itself. This is akin to demolishing a house by tearing its address and phone number out of the phone book. To be secure, you need to raze the house, remove the foundation, and plow under the remains. So then, what do you do?

A local attorney friend of mine once told me of his solution: he sent his son into the parking lot of his office, with the hard drives and a sledgehammer, and told him to have fun! You can certainly donate or sell the machines without the hard drives after you destroy them, but what if you want to include the drive to increase the sale revenue or the size of the tax deduction for the charitable donation? Or, as in my case, I had leased a laptop and needed to return it intact to the manufacturer.

The good news is, there are several utilities available to wipe your hard drive that meet DoD standards for security. Established software publishers provide solutions like Symantec’s Wipe utility in Norton SystemWorks or White Canyon Software’s Wipe Drive. There are also many share- and free-ware solutions out there like R-Wipe & Clean, Acronis Drive Cleanser, and Clean Disk Security. Many more are available through shareware download sites like tucows.com. These programs do this by writing zeros (at least three times) to the areas of the disk where the deleted files resided. If you work with a computer consultant, he or she might also have a utility they use. In any event, you need to make sure you employ one of these utilities if you do not plan to destroy the drive physically.