10-28-2012 02:48:05 PM
If the STB is wireless you shouldn't have any problem. If it is wired, then there needs to be a coax or Cat5 run from that room to the Residential Gateway.
10-28-2012 04:10:30 PM
If it does not work you need to check out the other end of the coax cable. It may not be connected because there was no TV there when U-verse was installed.
At that point you need to develop a better understanding of your house wiring. The first step would be to post what you see - all your connectivity.
Of course, if it works when you plug it into the wall outlet, you are done.