More my territory. With Partition Guru, you can just open up the disk in a HEX editor. If the drive free space is all 0s or a repeating sequence, then the customer might have done the "Prepare drive for resale" option. Typically when doing a reset, it will either give the option to "Delete everything" or to "Delete everything PLUS overwrite free space". If they did the latter, nothing can be done.its for a windows drive
I think it used to be freeware, the old versions you can find http://appnee.com/partitionguru-pro/Where can i pick up partition guru?