So you think all those old files that you deleted from your computer hard drive are gone forever right? WRONG! 

They are not. In fact, in many cases, even if you delete a file, empty the recycle bin, and reformat your hard drive, it is still possible to recover the data. I didn't know this until I bought a new computer and took the advice from a local computer data back-up company in town before I sold the old computers on.

I guess the good news about this is that if you accidentally delete important files and need to recover them. Using the right tool, you can probably recover the lost files without a problem.

On the other hand, this is bad news if you delete sensitive files and then sell your computer to someone who knows how to recover deleted files - especially if those files contain customer or financial data.

If you plan on disposing of your old computers like I have just been doing, you'll definitely want to use a multi-pass file wiping tool (ie BcWipe or Eraser 5) to securely clean your hard drives first. These programs work up to a 'military high security standard'.

You never know who might end up with your old computers or what they might find if they look hard enough, so be sure the files you deleted, are really deleted.

Better to be safe than sorry.