printer detected by CUPS, browser interface not working ...

[Joe Weinberg <jweinberg1975@yahoo.com>]

I installed a Canon imageCLASS D300 using its USB port

$ lsmod | grep usblp
usblp                  17090  0 
usbcore               171098  5 usblp,usb_storage,ehci_hcd,ehci_pci,usbhid

$ sudo /usr/sbin/lpinfo -v | grep direct
direct hp
direct usb://Canon/imageCLASS%20D300?serial=2289HKMc
direct hpfax

but I can't manage it via the browser interface. When I:

 a) try: localhost:631
 b) click on add printer
 
I get a authentication error: "A username and password are being requested", that I can't pass after trying many options

How can use set up the printer in any other way for okular, firefox or konqueror to be able to use it?

lbrtchx