upvc door closes but will not lock. The handle lifts so far and stops. with the door open all the locking actions work smoothly. it worked for a short period then stopped. i have oiled all the mechanism. I have not loosened or adjusted anything. i have checked the frame and door alignments.

bill bennett, November 2006

the other thing you may need to do is if the door has dropped on lock side you will need to toe and heel the door or if you have flag hinges you can alter it from them with an allen key

peter, December 2006

Try removing the lock plates off the door frame, one at a time, ie remove top one and try locking door, if door locks this is your problem one, if not replace it and remove the next one down and try again. Repeat the process for all of them until you identify the problem one, there's about 4. Check the plate for damage, burrs or a rough surface and also check the corresponding bolt part on the door itself.

Colin1970, November 2006