One of the challenges of successful data recovery is to be able to "see" the drive data on our recovery equipment. That can only happen with a direct SATA connection to the drive so data recovery equipment can "talk" to the drive through the SATA connection on the board. (SATA is what the standard type of connector is called on both desktop and laptop hard drives. It has a separate power connector and a data connector.)
What happens if that drive is one of the newer USB 3 external hard drives? These drives do not have a SATA connector, but a USB 3 connector--you know, one of those weird looking connectors with the crimp midway across the bottom part. Well, this is a challenge because USB connectors rely on circuitry that doesn't allow data recovery equipment to effectively "talk" to the drives. The only way to recover the data on a drive that does not have specific hardware damage--i.e. clicking, is to solder SATA connectors to specific points on the drive circuit board.
Challenging, no doubt about it, and something that makes data recovery from these convenient and popular drives a bit more complicated. At TechPort, we are working on solutions to these types of data recovery challenges.