*HELP* Receiver not outputting video after power outage

[My_Two_Cents]

From page 98 of your manual:

If the video source is connected to an HDMI input, you must assign that input to an input selector (page 39), and your TV must be connected to the HDMI OUT (page 23).

This is the only thing I can think of that you might try. I sounds like you just don't have the signal paths set up properly, but I can't imagine it would be this difficult to figure out. When you run out of options, then it's probably time to call Onkyo support. Sorry I can't be more helpful.