Hi, I had kernel panic problems with my mac pro and brought it back to the shop where I bought it. Before doing so, I erased the hard drive using the 7 passes method. I got back my computer and found in the trash a video I had before erasing. I'm wondering how just a simple video survived the 7 passes and if they used a program to recover erased data wich would be absolutely fraudulent. Is there a way to find out if a recovering has been done? Thank you.