Hi, I have just installed Plustek OpticSlim 2400 usb scanner. I added this line to /etc/hotplug/usb/libsane.usermap # Plustek|OpticSlim 2400 libusbscanner 0x0003 0x07b3 0x0422 ...(zeros as in other lines)... Without this line I was unable to use this scanner from non-root account. I hope it helps someone, Jan Matousek