Not the most common error but it still does occur on these printers. Obviously, the first thing to check is the feed separation rollers (part# RM1-0037) The rollers for the 4200 and 4300 series tend to last a lot longer than original 4000 rollers but they still wear out so check to make sure they still have tread.

I see a lot of third party rollers for this machine that are either oversized or the rubber wears out sooner than the OEM’s so look for rubber debris below or around the cassette roller and check to make sure there is still tread on the rollers. If you think the rollers look like third party rollers your best bet is to just replace them.

While a lot of third party rollers look OK they can cause lots of odd feed problems in printers. Another thing overlooked is the actual pick up roller (Tray 1 part# RL1-0019), Tray 2 & 3 part # RM1-0036) and sep pad (part # RL1-0007) behind the top feed separation roller. Overtime the rollers get a glaze on them. Or, once these machines get about 400,000 to 500,000 prints the pick up roller wears out and needs to be replaced. These rollers aren’t included in the printer maintenance kits (4200 model printer maintenance kit part# Q2429A; 4240, 4250, 4350 models printer maintenance kits part# Q5421-67901; 4300 model part# Q2436-67903).

Also check the paper stop in back of the tray, remove the paper and make sure the stop indicator is lined up with the size indicator on the tray. People like to push these forward too far because they see a gap in the front of the tray. If pushed forward too far it doesn’t allow the paper to lift properly and feed up into the machine.

Remove and reinstall the paper to make sure it is installed properly and that it’s not folded over in front of the tray. If you are still having issues, remove the back dust cover and with a flashlight watch how the pick up assembly is operating.