I wanted to change the light fixture in my front closet. Simple enough task. I've done this sort of thing hundreds of times.
I turned off the circuit breaker. I took the old fixture off. However, I found that the wires were whole with only a small piece of the plastic/rubber covering peeled off from the center from each color. One wire was white and the other yellow. There are no ends to you would typically find. I thought it was odd but just went with it. I wrapped the white wire from the new fixture to the white wire in the ceiling and the black wire from the fixture to the yellow in the ceiling. Long story - short...When I turned on the electricity the circuit blew. Needless to say what i thought would work, didn't.
I hope all that makes sense. I have not idea how to resolve this, considering it should have been easy.