I am attempting to recover data from a Hard Drive that doesnt show up in the disk utility. I currently have it connected using an external hard drive cable.(usb to sata) Is there another adapter that allows the hard drive to be recognized differently? Is there any software that can force the hard drive to be recognized by the system? It sounds as though the read/write arm is moving back and forth across the platter repeatedly. Does this mean that the hard drive is not salvageable unless i send it to a recovery company?