Many times I’ve had to replace this door latch assembly. Often it comes with the three micro switches you see in this picture courtesy of Reliable Parts, sometimes it does not come with them.

The indication that this may need replacement is when the microwave blows fuses or trips breakers when the door is opened or closed. If you look up the two shafts that the doors latch hooks glide up before dropping into place you can see that one side is worn down which results in the micro switches not closing in concert which leads to blown fuses.