Digital Cable Set Top Box

I cannot get Media Center to recognize my Motorola digital cable set top box.
I can find one channel...channel 3 that Media Center has to stay on to view
the digital cable.

I get an error when setting up the TV signal that says "IR Hardware not
found". I have the system set up just like Media Center says to do, but I
cannot get it to work.

The coaxial cable from the wall connects to my set top box. The set top box
is set up to my PC's TV tuner. I put the IR cable from the Media Center PC
to the front of the IR on the set top box. I cannot complete the setup
wizard because it cannot find the IR signal. Anybody have any suggestion?