My garage door remotes do not work even with new batteries, help!?

Make sure the remotes and the garage door sensor are coded together. Also, if you have a garage button in the garage, make sure the lock button isn't on if yours has this feature.

First, like Superb said, make sure the lockout button isn't activated. If, when you push the remote, only the lights on the opener flash, then it has been locked out. Otherwise...

They may have lost their code. Most openers made since the 90's have a programming button on the control panel. You push the button once and release it. Then, push the corresponding button on the remote control you wish to program. (You may have to push it twice)

That should do it. Refer to your owner's manual if you need to. If you don't have the manual, go to the website of the manufacturer. You should be able to download the one you need.