We've tried all of the support available online, including powering down the modem for 5 minutes. The wireless box turns on and we see the instructions to pair but after pressing the "Ok" button on the unit and the WPS button for 10 seconds on the modem, we get a scree that says "We're sorry, something isn't right...". The power button is green on the wireless box and there's a red light beside it.
This happened suddenly to all 3 of our wireless boxes and we're seeing the same error on all of them.
If I recall, the T1200H uses an additional antenna (VIPxxx) for TV signal. If so, have you tried using it to reconnect?
It also might be time to request a newer router for your home. The T1200H is at least 2 generations old.