I bought a Samsung 1.5 TB Hard drive and plugged it first into an enclosure related to my computer by an USB 2.0 port (I have also USB 3.0 ports on this computer). This enclosure worked perfectly with another hard drive. Immediatly, the external Samsung hard drive made a strange noise (like "tak, tak, tak") and it couldn't be formatted. From time to time, the noise stopped and was replaced by an apparently "normal formatting noise", as if some sectors of the drive were correctly read. As the disk could not be formatted, it was not identified and it was not given a letter. I tried then to plug this hard drive directly in the computer (in slave mode; anyhow it was selled without any jumper) and I got exactly the same result (noise "tak, tak, tak" and so on). For me, it's clear that I've been sold a defectuous device, but I am not a profesionnel and Samsung says that defectuous devices are very rare. I also tried to use the Samsung tools to detect the problem, but with no result (event Samsung tools did'nt identify my Samsung hard drive...). If anyone has experienced the same problem, I vould be grateful for help or confirmation of my diagnostic.