Recently I decided to watch some sports on WMC. After attempting to watch TV on Windows Media Center, I kept getting the error, “Viewing or Listening Conflict, No tuner to Satisfy The Current Request”. I tried to reinstall the HDHomeRun drivers, I tried to scan all channels again. It seemed everything I tried would not work, and Google was not being much help.
Then I remember that I recently upgraded my home WiFi Router and dug in to it a little bit more on that front. I found that since WPC is always in the foreground, when then network changed, I never classified the network type (Home, Work, Public). Windows by default will set any new connection to Public for security concerns.
I went in to my network settings, updated it to Home, and voilà my TV tuner now works again!