Tray <x> Low
What this message means:
The specified tray is low on paper.
What you can do:
Add paper to the tray to clear the message.
See also:
Loading the trays
Tray <x> Missing
What this message means:
The specified tray is either missing or not fully inserted into the printer.
What you can do:
Insert the tray completely into the printer.
See also:
Loading the trays
USB <x>
What this message means:
The printer is processing data through the specified USB port.
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