recepitable for microwave

I thought the OP was simply looking at a replacement recept. If there's no power to it, I removed a recept. in our old TT and found that the wires on the back were barely hanging on to the "stabs" at the rear of it. The wires need to be pushed down into the slots all the way, and it *could* be possible that a wire that has come off. Not sure if microwaves are always on a dedicated circuit, but if it is, either there's a problem at the panel or at the receptacle and should be easy to find the cause. If there's no power at the receptacle, a recept. does not go "bad" so maybe there's nothing wrong at all with the 20 amp one that's in there now. The Romex wire could possibly be severed or damaged somewhere, but that's rare. You could get a non-contact voltage tester (NCVT) as a diagnostic tool to try and trace back where power is and isn't.