I did this and it worked!mjr0483,
I had this exact problem today and figured it out. The online manual states if there is something obstructing it, it shuts off. To reset it, here's what I did. There is a small black box under the track where wires run into both sides. On top you will find a red switch. Switch it in the other direction, leave for a few seconds, then switch it back. Then pull the door all the way back until it clicks and locks. Make sure it doesn't slide forward at all. Then pull the handle out and slide the door to the closed position. When closing, you should feel some resistance. When fully closed, try the button then. Hopefully this will fix it. If not, could be another deeper issue. Hope this helps!