Nope. Most people still belive that magnets harm computers. They did in the old days when we used floppy disks and such but now it wont.
I am misleading a magnet will harm components but it must be very powerfull. They have degaussers that will kill harddrives for you they are essentialy a big electric magnet that scrambles and frys the harddrive. You wont be able to do it with any magnet you have laying around your house.
BTW deleteing files does leave a footprint but in most cases I think would be very hard to recover. So I would not worry about it unless you were hosting a ring of child pornography and the FBI is after you.
Gunners right, there are two schools of thought here. I perform data recovery services through my computer company and can tell you with certainty that formats can be recovered up to 7 deep with software alone. Even degausing is no barrier to a Level II Cleanroom "forensic" recovery though. If you've really been naughty and the government gets involved, there is just about nothing their programs and procedures can't recover.
Think about data recovery from the Space Shuttle and airline tradgedies and this becomes apparent. But these are EXTREME examples. A DOD wipe of the drive is somewhat effective, but can also be "descrambled".
Moral is, if your doing something THAT illegal, stop.
Dang I hate being such a messenger of doom ::)
Take care friend,
Mick

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