I had problems initialising the SDD drive in the optical bay. But have placed it in HD bay and it works fine.
My old Hard drive is a really snug fit in the caddy (its a 9.5mm drive) - when installed in the HD bay it sits on rubber shock absorbers and has air around it.
With a HD in the optical bay, I expect there to be some overheating or shock problems in the future.
Mine too. I'm going to retry back in original position which is less likely to overhead or be shocked because no rubber mounts
Failing that buy a WD 7mm drive which is not ideal.
Also had this same problem. Tried and failed a Samsung firmware upgrade. Ended up send drive back to Amazon.