Lexmark MX310
You may need to order an imaging unit. If necessary, select Continue on the printer control panel to clear the message and continue printing. For non‑touch‑screen printer models, press to confirm.
Understanding imaging unit yield on Lexmark's MS/MX 310, 410, 510, 61x, 71x, and 81x devices.
31.6x Error Code Reinstall Missing or Unresponsive Imaging Unit (IU)