Old Computers and Sensitive Information

Photo credit: mike73 from morguefile.com

Have an old computer that you are ready to give away, sell or dispose?  Most likely you will have sensitive information on that machine.. maybe emails, passwords, financial records, tax returns?  What can you do to keep this information from getting into the wrong hands?

A word to the wise:

• You cannot just delete your files and empty the recycle bin.
• You cannot just format the hard drive.
• You cannot just format and reinstall the operating system.

In each of these cases, your files can be recovered.

There are four ways to make your hard drive files completely unrecoverable and your data safe from being compromised.

1. You can remove the hard drive and physically destroy it.  You would need to completely destroy the individual plates and not just the hard drive case. It is amazing what can be recovered on a hard drive by experts. This requires power tools, chemicals or you can purchase a kit called DiskStroyer: Hard Disk Destruction Kit.  
2. You can choose to degauss the hard drive. This is a process that uses a reverse magnetic field to scramble the electronic data and make it unreadable. Unfortunately, this machinery is expensive so you would have to contact a professional to provide this service.
3. There are a wide range of free and commercial utilities, such as Active@ KillDisk that will erase your data by overwriting the entire drive.  If you are comfortable with changing your boot drives to a USB (by going into the bios) you can erase your information. Please keep in mind that this will also erase the operating system, but of course, you backed that up when you first purchased the computer, right? (Step one... always back up your operating system.)   If you aren't comfortable with doing this on your own, contact your local tech person, such as McAllister Park Design (shameless plug).
4. Last, if you didn't heed the warning to backup your operating system, you might want to consider software that virtually shreds your files.  Programs such as Shred 4, claim to make data completely unrecoverable. Now, you have to be sure you have removed all the files. File shredder software only secures data that is being or has been discarded. 

If you have a Mac, it comes with a file shredder type/secure deletion program built in.To securely delete a folder or file, move it to the trash can and from the Finder menu select 'Secure Empty Trash'.