I have a Canon Pixma MP600, which is supported by xsane with pixma backend.
I have Xubuntu 12.04, this is the result of sudo sane-find-scanner -v command:
searching for USB scanners:
checking /dev/usb/scanner... failed to open (Invalid argument)
checking /dev/usb/scanner0... failed to open (Invalid argument)
and so on.
checking /dev/usbscanner... failed to open (Invalid argument)
checking /dev/usbscanner0... failed to open (Invalid argument)
and so on.
No USB scanners found.
It works on my laptop with Ubuntu 12.04.
How to fix this?