As Aaron suggested I also think you installed your printer with the usb backend instead of the hp backend. hp-toolbox GUI needs the hp backend to work! Run the following command to find out which backend you use: $ lpstat -v The recommend way for installing a printer in Dapper using gnome-cups-manager is described here: https://help.ubuntu.com/community/HpPrinterInstallationAndMaintenanceDapper
-- hplip cannot find DeskJet 5440 printer, despite CUPS's claims to the contrary https://launchpad.net/bugs/49107 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
