You obviously have a different computer so what you do is google Darik's boot and nuke. follow the instructions to burn the .iso file to cd then use it to boot with .... BE AWARE it will erase all the hard drives that it detects ... so if there is more than the one you want erased plugged in then unplug the power cord to the drive before running DBAN, it will take a while but EVERYTHING will be gone.