Fixing the Latches
Open the dryer door. Inspect to see if anything is caught in the path of the door that might cause the door to keep popping open. Tighten the latch screws with the Phillips-head or flat head screwdriver. Check to see if that was the problem.
Remove the single latch or multiple latches from the drying machine by turning the screws holding the latches in place counterclockwise with a screwdriver. Discard the old latches.
Insert the replacement latch or latches in the same position as the previous latches. Replacement latches can be purchased at appliance hardware stores. Screw the latch screws clockwise until they are firmly in place. Close the dryer door to ensure the latches are working properly.
Replacing Door Switch
Unplug the drying machine for safety purposes.
Open the dryer door. Locate the door switch and actuator lever, which pushes in the switch when the door is shut allowing the drying cycle to start. The switch and lever normally come together as a set of replacement parts.
Unplug the wires of the switch that are connected to the dryer. Unscrew the screws holding the switch in place with the Phillips-head or flat head screwdriver depending on the make and model of the dryer.
Insert the replacement switch and lever in place. Turn the screws clockwise until they are snug. Reattach the switch wires to the dryer.
Plug the drying machine back into the wall outlet. Close the dryer door and test the switch and lever to make sure it is properly working.