You might look up the dickhead IT guy that changed it to begin with. If you tried supervisor>no password and that didn't work, I don't know what else...
check the lower roller and upper roller bearings. If they are not in the right way they cause excess torque to turn and usually just skips and breaks...
I had an install a few years back and while giving the customers some training a lady needed a copy. She loaded her document into the ADF and pressed...