DIAGNOSIS A sensor flag is likely stuck in the 'blocked' position, or a small, torn fragment of paper is obstructing a sensor. Common locations are not always visible without disassembly.
FIX Power off and unplug the printer. Open all access doors: the rear output tray, the front cartridge access door, and the duplex unit (if equipped). Using a bright flashlight, inspect the paper path. Pay specific attention to the area behind the cartridge carriage. Look for any debris or a stuck sensor arm. Use a pair of tweezers to remove any fragment. Manually rotate the white paper pickup rollers inside the main tray area to check for smooth movement. Plug the printer back in and power on.
IF THAT DIDN'T WORK A faulty paper jam sensor may be triggering the error. Perform a 'cold reset'. With the printer on, simultaneously press and hold the 'Wireless' and 'Cancel' buttons on the control panel for 5 seconds. The printer will restart and run internal diagnostics.
HEADS UP Do not use excessive force to pull on any internal components. If a sensor arm is broken, the error will persist and require a service call. Using paper that is too heavy or has ragged edges increases the risk of tears that cause false jams.