a system and method for first changing the encryption key on a self - encrypting disk drive followed by a complete disk wipe . either process can be separately performed , and they can be performed in any order . in fact , one embodiment of the invention , resets the symmetric key , wipes the disk a predetermined number of times with different predetermined data patterns , and then resets the key a second time . this assures that there is absolutely no way to recover the original key or to read the original plain text data , even if some of it &# 39 ; s encrypted values remain on unallocated tracks after wiping . a user can be assured that in milliseconds after starting the wiping process , the entire disk is rendered unreadable and unrecoverable .