The easiest solution to this is to check for a built-up ridge of dirt (sludge, grease, etc.) on the back of the track. The doors will open, but the rear door roller will ride up on the small mound of debris on the back of the track. Then when the door drive turns off, it will roll back down it a slight bit and generate that error.
Or, the door is actually simply not reaching the end position it learned when it first did a learn run.
Good luck.
