Did you know that files are not actually removed from your hard drive when you delete them in Windows (I don’t know about other operating systems, but I think they’re the same), even if you empty the Recycle Bin?
The files and folders you “delete” are actually still on the drive, except they’re hidden. This was implemented into the file system to allow for a much faster deletion speed (it takes quite a while to completely delete a file, about 5 minutes per GB on newer hard drives) and to give the user a possibility to get his data back in case of an accidental deletion or quick formatting (full formatting removes all data, but can take up to a few hours to complete).
So, if you have any sensitive data and think that you can delete it anytime if the circumstances require it, you are in for a big surprise. Using a data restoration utility like Norton Save & Restore or R-Studio, anyone can undelete your files and open them, exposing all your secrets.
Let’s say you really don’t want that to happen. How should you proceed?
One way to do it would be writing unimportant data like music and movies over the deleted, now hidden files. This would physically remove them to make space for the new ones. But you wouldn’t know where exactly were they written on the surface of the disk (they could be at the beginning, middle, end, or scattered all around if your drive was heavily fragmented), so you’ll have to fill all of the free space with unimportant files to be sure they’re really gone.
Another, simpler way to proceed would be getting a special utility that would completely delete any files you want. And you won’t have to pay a small fortune to get it either, because there are a lot of absolutely free programs around.
One of the best is DeleteOnClick, a small but powerful complete removal utility that follows the United States Department of Defense 5220.22-M secure file deletion standard, which guarantees that your files will never be recovered. The freeware version is more than enough for home and office users, while the commercial version provides even more security by deleting all headers (special sections on the hard drive that store information about everything that was written and deleted, like a log) from the disk and can wipe all your free space at once (to ensure you delete absolutely everything).
To download and install it, go to http://www.2brightsparks.com/onclick/download.html , scroll down a bit and click the Download button next to “DeleteOnClick Freeware version”, after which run the installer. You’ll need to restart your computer after installation, because the program adds a new right-click menu to Windows, called “Securely Delete”.
When you need to irretrievably delete a folder or some files, just select them and instead of clicking “Delete”, click “Securely Delete”. It will take quite a while, as the utility basically replaces the files with useless data, then deletes it, too. Think carefully before doing it, as you will never be able to restore those files again!
This is it, now you know how to securely dispose of important data to keep it from falling into wrong hands. I hope you will put this information to good use.