"Restore Now" returns most printer settings to the original factory default settings. Exceptions include the display language, custom sizes and messages, and "Network/Port" menu settings. All downloads stored in RAM are deleted. Downloads stored in flash memory are unaffected. Press Menu (Wrench button) button.
Even premium printers like Canon can develop problems after being used for a prolonged period. It is possible to do a hard reset canon printer after using the printer for some time. This would involve changing the settings so it works properly again.