I have experienced my drivers door not opening from the outside and inside, but never both at the same time! On two occasions, in really cold weather the central locking opened all doors except the drivers door. This lasted a few weeks after which it miraculously worked again. Audi quoted me £400 to replace the lock, but I just wait it out. The inside failure was just a snapped cable, which was relatively easy to replace. A couple of obvious questions. Have you tried opening it with a key? The other thing to try is the MMI allows you to select what doors are opened by the central locking, front only or all. Try toggling it a few times to see if that changes anything. Sorry, but can't think of anything else to suggest. The bolts that secure the lock are only accessible with the door open, so it's a catch 22 situation. I wonder what an Audi dealer would do? It may be worth asking them, they may give you some ideas.