That is a step I plan to try down the road. Right now I plan to try Disk Warrior as it can 'see' the drive but not access it. I ran Disk Utility - First Aid but was stopped by an 'Invalid Sibling Error'. Some Googling has suggested that Disk Warrior may work. I have not tried a format yet of the drive but I am hoping to pick a few files off the drive for the previous owner before I go down that road.