When the garage door keeps going back up when you try to close it, it may be a problem. Like a computer, your garage door has a logic board. The logic board is your garage door opener's brain and even with machines, a brain can wear out over time.
If your garage door remote doesn't work, you can replace the batteries and it will work again. An electrical surge can cause a breaker to trip. If the breaker that powers your garage isn't in the "On" position, you should check your home's breaker panel.
You should check the wall panel near the entrance of your home to make sure that it has been corrected. The open and closed limit settings are what garage doors have. When your garage door is completely open and when it is completely closed, these settings tell you how far up the track to go. The garage door stops if it reaches the open or closed limit. You may have to adjust your closed limit settings if your garage door keeps opening by itself. If the settings are too high, the opener will think that a door has closed too early when it touches the ground, and will mistake it for an obstruction.
You may need to adjust the limit screws if your garage door won't close all the way. The contacts on these screws tell the garage door opener how far to open or close. It is possible that a garage door refusing to close is a bigger issue than just fixing the sensor, cleaning the tracks, or resetting the travel/limit setting. It is probably time to call in the professionals when it is not a common issue.
There can be pressure and wear on door tracks. If your garage door is malfunctioning, call a service to have the tracks replaced. The shut reverse, where the door closes and then comes back up, is a wackier malfunction that happens with some doors. Problems like this are caused by a misadjusted limit setting on the opener. A dead transmitter remote is a minor problem, but a common reason your garage door won't open often is because the batteries have died.
The limit switch needs only a flathead screwdriver if your garage door isn't staying open. LiftMaster has a helpful resource about how to adjust a limit switch.
Garbage cans, shovels, and even mice can cause damage to the wiring. Since the wiring is low voltage, small electrical signals can cause the opener to run. The opener's logic board or the motor unit itself may be to blame when the door starts to descend on its own. Similar to your travel down setting, your garage door opener's limit switch governs where your garage door stops when raised or lowered.