All of a sudden, the water stopped dispensing from the door. I replaced the water filter, but it didn't help. When I press in the lever to dispense, I hear a click from the refrigerator, but no water dispenses. Ideas?

It may likely be your water inlet valve has gone bad. Take off the back panel, unplug the connectors to the valve and measure the resistance across the two coils (one for dispenser, one for icemaker). Should be around 200 ohms each. There are a few youtube videos on how to do this.