If your home's entryway doors are uneven and don't close or lock properly, or you always hear an annoying squeak, creak, or groan every time you use them, you may not need to replace them or even call a door repairperson. Sometimes just a few simple fixes can be enough to get the door and the lock working again. Note a few of those fixes here so you can try to address them on your own before calling a contractor.
1. Sticking of the door
One of the most common reasons for a door to stick at the top or bottom is that the hinges have come loose. Note the hinges of your home's door and if the faceplate, meaning the piece attached to the door's frame, is loose or crooked. If so, the door will also be hanging crooked and will stick to the doorframe. You can tighten the screws of the hinge faceplate but if those screws are plastic and thin and a bit flimsy, they may simply come loose again, as they're holding up the weight of the entire door. Remove them and take them to the hardware store and get strong metal screws of the same size as a replacement.
It may also be that your wood door has expanded from absorbing moisture. You can use a wood plane and simply shave down the stuck area; be sure you go slow and only remove a very thin layer before putting the door back into position and noting if this fixes it. Otherwise, you could go from having the door stick to having a large gap at the top or bottom.
2. Lock sticking
As with the hinges, if the faceplate of the deadbolt has come loose from the doorframe, it will start to come out of position and the lock or bolt won't slide in very easily. If the wood around the faceplate has gotten soft, you may need to add some metal brackets to the inside of the area around the faceplate and then tighten the screws, to keep the entryway for the deadbolt in place and keep the lock from sticking.
Squeaking is usually a problem with the hinges themselves. You can try some lubricant, but often this means the door's weight has bent the hinges out of shape and the metal pieces are now rubbing against each other. It can be good to simply replace the hinges altogether, preferably with something stronger that will be better able to hold up the weight of the door.