The door on our 7 year-old Frigidaire microwave was broken by the handle. It was still functional as a door, but unsightly. We were all tired of reaching for the door only to pull on the handle and have it flap around without opening the door.
The fix was really easy. Just remove two screws that hold the fascia piece in place above the door, lift the old door off its hinges, place the new door on the hinges, and replace the fascia and its two screws.