Emerson Microwave. I have an Emerson MW8115SS microwave. It was given to me by a friend not too

Question

I have an Emerson MW8115SS microwave. It was given to me by a friend not too long ago. The microwave turns on with the door open, but when you shut the door it blows the breaker in the house. I removed the cover and the fuse is good. I removed and tested the door switches and they are good as well. I used a DVM to probe voltage and I get voltage to the HV transformer 200vac. I have tried it numerous times and it throughs the breaker in the house every time. My assumption was that a power wire was grounded somewhere inside, but I did not see any wire problems anywhere. I need some suggestions to get this thing fixed. Thank you.