TurboPrint & PrintFab

Just tried to install a Canon Pixma MP 450 under Ubuntu 6.06 (Dapper)
usbcore and usblp are loaded

Trying to print a test page with xtpsetup says that the printer is not connected
I tried devices /dev/lp0 usb://Canon/MP450, none works.
Alors /proc/bus/usb remains empty, and /dev seems to contain no usb device.
Seems like the printer is not even detected and that some kernel module
is missing. However, I found no indication from Turboprint, though the
Canon PIXMA 450 is said to be supported. What can I do ?

We had a similiar report for Ubuntu Edgy / Feisty - the usb backend cannot access the usb device:

I have a similar problem on an MP600.

I solved it by checking the permissions of /dev/usb*

Turned out that cupsys runs as user "cupsys", which needs to be in group plugdev. This is on Ubuntu Feisty. So check

ls -l /dev/usb*
ps aux |grep cups
grep plugdev /etc/group

If that is the case for you, you need to

adduser cupsys plugdev