When I got my D it was in parts and the door either stuck open or did not close, today they operate perfect. I the process of aligning them they got stuck numerous times. I was always able to open them buy placing a flat prybar between the bottom of the door and the bottom of the door opening, with the proper force they would open up, of course I was very careful and took precaution not to damage the door buy placing the right shims on the prybar(cedar shingle) if this buy chance does not work u may have to release them manually from the internal mechanisms.