I have an outlet in my kitchen, inside one of the cabinets. There are two receptacles on the outlet. One works and one doesn't. I've located the breaker switch for the outlet. It's dedicated to my microwave oven. Is this a faulty outlet, or maybe another issue?

Thanks

It could be the outlet.

On a typical outlet the two receptacles are connected by brass tabs. If you want to make one receptacle switched you'd break the tab on the black side.

With the power off, carefully check the outlet to see if you see these tabs, they'd be between the screws on the side. I say carefully, because you could also have a "multi-wire" circuit here. In that case you'll find the tab missing and a red wire on the screw next to the black wire. In that case STOP. It might be live. You'll need to find what breaker supplies power to that side.