Computer's?
Answers:
Format the hard drive, then install windows.
There's a lot of software out there that will come close to this for you. Try System Mechanic 6, or 7. I say close, because the government has software that will find your info, even after using a 'blowfish algorythm',(probably a lot of hackers out there too!) The only true way to fully delete your information that's left on your harddrive, is to melt the disks inside to a blob. Even using a hammer on the harddrive may not fully delete your info!
Grab a screwdriver and pop the cover off the drive. Poke the screwdriver into the case between the first platter and the platter immediately below it. Pry up until the top platter bends at least 45 degrees. Move the screwdriver 1/4 of the way around the case and pry up again. Repeat this process for all the platters.
Pick up a piece of steel wool. Apply the steel wool in a vigorous scrubbing motion to all the exposed surfaces of all the platters, being sure to affect both sides of each and every platter.
Prepare a salt bath of 1 part salt and 10 parts warm water. Immerse the drive into the salt bath for at least 24 hours.
Viola. No more data.
the absolute way is using a program called evidence eliminator.It has proven up to military standards, and is imposable to get the data back.
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