So a circuit in my home is dead. It covers a couple lights and a couple outlets. I plugged a microwave into this circuit and it was more than she could handle. Before this, the circuit worked fine for years, but the lights would noticeably dim when the load from the toaster was applied.

The breaker is not tripped. I replaced the breaker. This particular breaker was different from the others, not labeled on the panel, and the romex enters the panel from a different direction than the other 20amp circuits; I suspect this circuit was added after initial construction.

There is no GFCI on this circuit. The fixtures and outlets are all standard with no obvious fuses. There are no scorch marks, and there was no smell when the circuit cut out.

I worked as an electrician's assistant when I was a teenager. I have basic skills and basic tools. I don't have an outlet tester or a mutimeter.