A factory reset should be performed every time the firmware is flashed or a component is installed or removed from the printer. The factory reset forces the printer to rescan the hardware bus and updates the configuration of the printer.
HP Deskjet 1220c and Deskjet 1180c Professional Series Printers - Factory Reset Information and Instructions
How to factory reset the printer
Follow the steps below to reset the printer:
Turn off the printer.
Press and hold down the RESUME button and then press and release the POWER button to turn on the printer.
Release the RESUME button after the printer initializes.
Printer behavior if factory reset is not performed
Unexpected printer behavior may occur if the factory reset is not performed after flashing the firmware or installing or removing a component. This example involves a printer that was upgraded with a network and personality card. The following behavior occurred:
The LCD displayed the message Load plain paper.
If the personality card was removed, the printer performed normally.
A factory reset corrected the problem.
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