Using 12.04; I recently added a USB connection for Arduino board. Now I can not print using a Canon ip2600 printer. It is shown as installed but if I try to uninstall or update properties I get a request for a password which is rejected regardless of what is entered, my username is a member of admin and I added it to lp group but I still can not print. The print queue shows that the printing was completed but it was not. I am not allowed to empty queue and no update of drivers is shown in the print box. Printer works fine if I boot into Windows so printer and USB cable are ok.