The garage wooden door has a standard mortice lock, which seems to be jammed in the locked position. The keys have no obvious damage and I have tried the lock with both keys from both sides, but the lock will not open. The key will turn about about 1/6th of the way around and then no further. I think if I forced it, the key would snap first. Is there any way to remove the lock without breaking the door down?

Phil, December 2015

You do not describe the door but no matter - presumably the mortice lock has a tenon that fits into a mortice slot in an adjacent door - you might consider forcing the two doors apart - or if that's not possible - from the inside - chiselling out the timber around the mortice piece and - once the doors are open - fitting a better quality lock and making good the damage on the mortice side.

Given that you might intend to do as I suggest then there's little point in not trying to force the key just in case that works for you.

Good Luck..., December 2015