I'm currently using a small form PC to decode and play content from HDDs.
In your case there may be other issues. 3TB is very large and may be USB 3.0. Try some USB 2.0 cable if you have it. Samsung TVs were 2.0 and some found this trick worked. There can be a size limit to what the TV supports so you have to put some other computer to work on it.
I have a Visio M551d-A2R Smart TV that will not recognize a 3TB Seagate external drive formatted in ExFat. Neither my Mac or Windows 7 OS's have an option to format the large drive in Fat32 (obviously). I have a 16GB thumb drive that is formatted in Fat32 and the TV recognizes that just fine. Is there a firmware update I can obtain to get the TV to recognize ExFat formatted drives or are they too large for the TV hardware to handle? Any ideas or information would be greatly appreciated.