Not sure if the best place for this question is TV or computers.

I have a TV tuner on my computer. When I was a cable customer I connected it to the incoming coax. Then used Windows Media Center to record TV shows.

I am now using Verizon FIOS. I connected the coax out from the STB to the tuner. When I try to setup Windows Media Center, it doesn't recognize the connection. During the setup phase, I can see the video in the test box. But when I go to the next step it says there is no signal. I've also tried using S-Video instead of the RF signal. Result was the same.

Any ideas on why FIOS would not work when cable does? My guess it that they contain something other than the TV signal that sets them apart. But no idea what or how to get around it.