One of our other Hp Laserjet 9050dn printer displays 'Output bin full and Jam paper. What could be wrong.

SOURCE: Blank print out

This is laser scanner error message. The document is not being read from the data being sent. This could be a loose or damaged cable or bad scanner assembly. You can open it up and look for loose cables or connections to the board but otherwise if the scanner assembly is bad, it may require replacement. This should only be accomplished by a service professional as it is not a user serviceable problem.

SOURCE: standard top bin full remove paper

Hi there is seems that the machine thinks there is too much paper at the paper printout exit. If there are printouts on the top of the printer remove them and the printer will start printing or the error message will go away. If there is nothing on top of the printer then where the paper comes out after it has printed you will see a black plastic lever type it is more likely to be in the up position without breaking it if it hasn't already been broken move it so it is in the down position it is on a hinge so be careful and it should sit at an angle. Once this has been done the printer will reset the message itself.

Hope this is help you oh if the arm is broken it will need replacing (just the arm)

Thanks J

SOURCE: HP 2600n printer

1-st of all remove the dark blue/gray top cover - from the back/top of the printer there are in L and R side 2 holes. Stick a slim screwdriver to release boath locks and lift it up. Under this cover U'll find 4 scrwes. Before lifting the white cover remove the R printer cover for removing the control panel cable. Once U remove the white top cover U can access the fusssing assambley.
Good luck.

SOURCE: jam in output bin

Make absolutely sure there actually is no paper jammed in there. 
I came to this page with the same warning, convinced I had a software glitch. Turned out there was a page accordion-folded down to the size of a pencil lead. I didn't know paper could be folded that small. 
Of course, everyone here may be a lot brighter than I am, in which case sorry to waste your time. But for me, the obvious first fix needed to be thoroughly explored before cursing HP and their machine.

SOURCE: standard top bin full remove paper

Greets!

Firstly, is the exit bin full of paper? If it is, just remove it.

If not, then it's going to be a sensor that recognizes the paper amounts in the exit tray. Check for broken plastics and possibly stuck plastic flaps in the exit tray.

If it's neither of those, try turn it off, unplug, then reverse.

Other than that, if no go, then it's an internal sensor issue. At that point, probably the best bet is to replace as repair costs would outweight a new unit cost most likely.