Tuesday, August 16, 2005

Delete Button Does Not Delete!

On occasion I wheel and deal at a computer swap meet. I'll pick up hard drives real cheap there. Of course I'm taking a chance when I pick up a drive off the ground or a blanket that when I get it home it will not work. Last meet I got a 80 gig hard drive for $3.00. It works, whoohoo!

When I plugged the drive in I was able to set it up as a 'd' drive and accessed all the info on it. It had belonged to someone that had set it up as a 'C' drive with WinXP.

WinXP has now got it set up so that you cannot just simply transfer the drive from one machine to another. To get it to work as a 'C' drive I had to reformat it and reload Windows. This of course wiped out all the previous information. Or did it?

The info stored on a hard disk is simply magnetic bits that are pointed north or south, on or off, yes or no, 1 or 0. Deleting files or even formatting a hard drive does not remove all the information stored on it. It simply removes the pointers that tells the reading heads where to go to find the requested info. As a result sensitive information like banking and financial records can still be accessed with the proper software. I have read that even writing over the previous file doesn't quite do the trick. A ghost image of the file can remain and a real pro can find and reconstruct the info.

So, the question is, what to do with old unneeded hard drives to protect yourself from any hanky panky with the info on it. One solution that is quick and easy is to smash it with a hammer making sure all the platters inside get damaged. But suppose the computer you use at work is about to go down the hall to someone else. Perhaps the laptop you use is about to be transferred to another department. They might be a tad upset if the hard drive has major dents in it.

I came across this page from Brown University that gives some tips and links to software (Some Free!!! Whoohoo again!) that solves this problem. I see some in the list for Mac and Unix. (which reminds me of the time my buddy Mike asked another computer nut if he liked Unix. The man replied, "No! I prefer women...")

I will suggest you be careful if you download and use any of these programs. It appears that some of them are designed to wipe out the whole disk only and not selected freespace, files or folders.