Is it safe to sell your old computer?

- May 09, 2014

You want to sell your computer or tablets. You wiped your data from your hard drive for extra security. That should be enough right? Well, according to some reports, it seems like deleting your personal data forever completely and thoroughly is almost impossible.

Here are some of the bad news:

1. "normal deletion of files in your operating system of choice really only purges their respective file references. In the interest of performance, the actual data is left untouched on the drive -- with the space it occupies marked as empty."

2. "there are techniques and equipment that can recover data from hard drives that has been "wiped" over with zeroes or random bits."

3. " Techniques such as Magnetic force microsopy (MFM) make truly deleting data from magnetic media extremely difficult mainly because of the inability of the hard disk write head to write in the exact same location along the magnetic track."

4. "Contrary to conventional wisdom, even "volatile" semiconductor memory retains some of its contents after the removal of power."

However, the author did mention that "Techniques such as hard disk wipes will certainly make an attacker's job much more difficult, if not prohibitively expensive." It is not that reassuring, but at least it will be more difficult if you have taken the steps to wipe your disk with the appropriate software. Just bear in mind that, it will be difficult but not impossible. The old ways of writing and burning letters after reading suddenly seems far more secure doesn't it!