I have Artec E+Pro scanner.
http://www.sane-project.org/sane-supported-devices.html. gives support as “minimal”. Debian 4.0 installation included Xsane but this gave “no device connected”. I'd like to scan using Xsane but am working through terminal to get connected. So....
Man pages referred to Sane, but terminal didn't recognize Sane commands, so I installed all the Sane options I could identify from Synaptic. Now Scanimage -L correctly identifies the device “device `artec_eplus48u:libusb:001:005' is a Artec E+ Pro USB flatbed scanner” but scanimage >..filename.. gives “open of device artec_eplus48u:libusb:001:005 failed: Invalid argument” Xsane opened in KDE (accessories,graphics) still says no device connected but xsane in root terminal leads to the same “open of device artec_eplus48u:libusb:001:005 failed: Invalid argument”. Thread TigerOC & binary dreamer Aug06 suggested checking users in the scanner group, I have done that. Man pages suggested commenting out all scanners except mine in /etc/sane.d/dll.conf. I have not done that yet- should I? I'm guessing that this scanner is supported after all but I'm missing something obvious- please tell me what it is!

Hi!
I don't know whether this will help because I have an Epson Scanner.

In terminal type
sane-find-scanner | grep 0x04b8

This will give a return i.e.found usb scanner |vendor-0x04b8, product=0x0110) at libusb:001:002.

Your scanner may have different entry for 0x04b8, and you may have to find out what 0x0... after grep is for you.

then enter
chmod 0666 /proc/bus/usb/001/002 (here you enter the 00 results from find scanner command.

Then go to /etc/sane.d/ and find epkowa.conf and follow the instructions in this file to enter what will activate your scanner from the above information you have found by the previous commands.

All this has to be done in root.

I hope this helps

Thanks! Will try that lot (when time) & let you know. So far everything else has been possible in Debian... hopefully a bit of faith & a lot of fiddling will do the trick.

Your suggestion + lots of reading led me to the source of the problem- sane has listed the E+pro and /etc/sane.d/artec_eplus48u.conf has a section devoted to it so commenting out the other bits was a start- but in the end it was the lack of directory and firmware in the location specified by the .conf that caused the "invalid argument". Creating the relevant directory + adding the firmware from the manufacturer's cd solved the issue. Thank you for your reply!-