Our garage door is a challenger photo sense model p1534. It will close with the wall switch but will not open and the light blicks on and off, nothing is blocking the sensors is there a reset buttom for th sensor our the whole unit. We can figure out why will it close but would not open.. HELP!

Press the unlock button.

HELP !!
If hkstroud's advice did not work, please post that here, so that he and others know that, and can advice alternative options!
;)

See if you can have some one push button to go up, and help lift the door. Maybe the spring is not helping the weight of the door. I forget the name of the switch right now, It senses excessive pressure, one for up and 1 for down. Good Luck