Does anyone know how to fix an automatic garage door opener ?

I KNOW!!!!!!!!!!!!!

CALL THE REPAIR GUY... DUH!

It must be in some sort of bind. If the door closes and the tension is too much it will automatically open. This is a safety feature of the opener in case someone happens to get caught in the door while is is closing.

im sorry it took me so long to answer i was at work. if the power went out, and you disconnected the opener, and used it manually, and when the power came back on, make sure you reconnected back with trolley, if you see the chain or belt moving but the door does not then the trolley is not engaged. if the chain or belt does not move, you may need a circuit board due to a power surge. you stated that it clicks or hum ms when opening make sure the drive trolley is not hung up on the bolts on the rail , and it has surpassed its limit due to the power surge

I'd have to agree with the first answer that lighting has eaten your motor.

Can't say if it will be cheaper to replace the motor or to replace the unit depends on what brand you have.

On the up side get a pro to look at it and give you an estimate for repair/replacement. Lighting damage is covered by your home owner's insurance. So your insurance should pay all or part of the cost of fixing it.

depends how your one works. it sounds like something has got bent and is now stopping the motor moving the parts.

honey lightning hit the motor

are the sensors working? it can be just the chain or i think the motor had died.

no