HP 720 Series User Manual page 58

Message
Unknown USB
device
Unsupported
printer
Unable to
communicate with
printer
Disengage photo
tray
Printer top cover
is open
Incorrect or
missing print
cartridge
Printer has a
paper jam.
58
Possible cause
The connected
USB device is not
a printer.
The printer is an
unsupported
device.
The printer has a
problem.
The selected
paper size
cannot be used
with the printer
photo tray
The printer is
open.
The printer
cartridge is the
incorrect model
or is missing.
There is a paper
jam or the
printer carriage
has stalled.
Solution
Disconnect the current USB
connection and connect to
your printer.
Disconnect the USB cable,
and connect to a
supported printer, such as
HP Photosmart or HP
Deskjet.
Check the printer.
Disengage the printer
photo tray, or change the
paper size.
Close the top cover of the
printer.
Install a new printer
cartridge, turn the printer
off, then turn it back on.
Turn off the printer. Clear
the paper jam, and then
turn on the printer.
hp photosmart 720 user's manual