Automatic garage door on its own

All of a sudden our 1/2 horsepower craftsman automatic garage door keeps opening on its own. I close it and shortly thereafter will find it up again. What could be the problem?

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This is almost always caused by a faulty remote.

Remove the battery from all remotes, including any stuck away in a drawer somewhere in the house.

If it no longer opens on its own you have narrowed it down to the cause.

Now replace the battery in one remote. give it time to see if the door opens on its own.

Keep doing this until you find the faulty remote, then discard of it properly.

Most cities have someplace you can drop off old electronics for disposal.