Live TV does not function within Microsoft Windows Media Center 2005.
If TV is not functioning under Media Center Edition 2005, please ensure the NVIDIA Purevideo Decoder has priority over other 3rd party video decoders that you may have installed. You may look up which decoders are currently present on your PC by downloading the following Microsoft decoder checkup utility:
If the utility does not work you may need to uninstall these 3rd party decoders via Add/Remove Programs in Windows Control Panel.
Also, please see the FAQ on known incompatibilities.