I discovered that the latch on my fantastic plastic Canon EOS Elan 7E had deteriorated, and the door had sprung open, exposing that roll of film (grumble, grumble.) Repair was an easy process, after acquiring a replacement latch off eBay. There’s a full howto write up on J. David Buerk’s website. Essentially you have to remove the latch cover (2 screws) and the front faceplate (5 screws), pop the old latch out and the new one in. I had to move the electrical contacts to the new latch as well, as those weren’t included on the new latch. The metal piece was welded on to the latch, so I used a couple dots of superglue to keep the contacts in place. Reassembled, and now everything seems fine. For reference, the Elan 7E is cross marketed as the EOS Elan 7 and EOS 33.