When tuning to a TV channel you recieve an error that says "Tuner Not Found"
Digital cable tuner is not working, has malfunctioned, or is not recognized.
Turn off the computer (On the Windows Vista desktop, click the start button, and then click the arrow next to the lock button and select the shut down option.
Restart digital cable tuner (if external) by unplugging the power cord, waiting several seconds, and then reconnecting the power cord.
Restart the computer.
Start Windows Media Center and tune to a TV channel.
If you receive the error message again, the Digital Cable Tuner needs a firmware flash or is defective.