Jammed lock

A jammed lock is one that will not let the door open even with its own key: the key will not go in, will not turn or turns without moving the bolt. It can be caused by a broken part inside the case, a damaged lock cylinder, an attempted burglary or a door out of adjustment that presses the bolt against the frame.

The first thing is to rule out the simple causes: push the door or pull it towards you while you turn the key, in case the bolt is under pressure. If it opens that way, the problem is the adjustment.

If it will not open, do not keep forcing the key or the handle. If you see marks on the cylinder or the escutcheon, someone may have tried to get in: take photos before touching anything. More under lock repair and jammed lock.