HP 510PS manual Problem. See Loading roll paper or Loading sheet paper

	Front-panel messages
Message	Explanation and action
Unknown ink cartridges.	The ink cartridges are not recognized by the printer as HP-
Press ENTER to continue.	approved, and there is at least one that is new.
	Press the Enter key.
Unknown paper format	The format (roll or sheet) of the paper loaded in the printer is
Reload paper	unknown.
	Reload the paper following the normal procedure, to solve this
	problem. See Loading roll paper or Loading sheet paper.
Unknown paper type	The type of the paper loaded in the printer is unknown to the printer.
Select paper type	Select a known paper type from the printer menu.
Unknown printheads.	The printheads are not recognized by the printer as HP-approved,
Press ENTER to continue.	although the printer can still use them.
	Press the Enter key.