To fix a door that doesn't latch, tighten any loose screws on the hinges, latch and strike plate; loosen the door knob; and lubricate the latch. If needed, realign the strike plate with the latch by filing the plate with a metal file.
- Tighten the hinges
Lift up the sagging door to its right position, and tighten the hinge screws by turning them clockwise with a screwdriver. For the stripped hinge screws, unscrew the hinges from the door frame, and drill screw holes afresh so the wood dowel is slightly bigger than the new holes, and hammer in a new dowel. Reattach the hinges, and drive the screws into the dowel. Close the door, and test if it latches.
- Tighten the latch and strike plate
If the door does not latch after tightening the hinges, open the door, and check the latch and strike plate for loose screws. Tighten any loose screws with a screwdriver, and test the door again. If the latch does not work, loosen the door knob, and lubricate the latch.
- Align the strike plate with the latch if necessary
To align the latch and strike plate, grind the strike plate with a metal file until the latch fits in properly. Alternatively, relocate the strike plate to the position where it aligns with the latch.