Ok, I finally got it working, adding the udev rule from tools/udev in the sane- backend source tree.
The complete things I did as root : mv /etc/sane.d/plustek.conf /etc/sane.d/plustek.conf.tmp mv /usr/etc/sane.d/plustek.conf /usr/etc/sane.d/plustek.conf.tmp chmod 660 /var/lock/sane chown david /var/lock/sane reboot and it was working. Thank you very much. Source : http://wiki.archlinux.org/index.php/USB_Scanner_Support David
