Just bought ipod on e-bay (china) and not recognized in itunes. Cannot sync but the device shows on my desktop. What to do?

Thanks. I was able to turn off and restart ipod, but still have same problem. I think my ipod is a new (reconstructed) 7th generation w/new hard drive, casing, face plate, wheel, etc. I don't know if the parts (from China?) is creating the problem. When I plug into the port, the ipod icon appears on desktop, but I cannot open (and does not appear) in the itunes app. I'm lost.