Hi Staedtler, I knew You were right, but I gave it a try; too bad Brother sold a linux supported product while in fact they give no support, and not a good after sale service for a 10 months old product. This is (in short) the debugging output: 'sane-find-scanner' output -------------- snip ---------------- found USB scanner (vendor=0x04f9 [Brother], product=0x035d [MFC-1910W]) at libusb:002:006 -------------- snip ---------------- 'scanimage -L' [sanei_debug] Setting debug level of dll to 255. [dll] sane_init: SANE dll backend version 1.0.13 from sane-backends 1.0.27 [dll] sane_init/read_dlld: attempting to open directory `./dll.d' [dll] sane_init/read_dlld: attempting to open directory `/etc/sane.d/dll.d' [dll] sane_init/read_dlld: using config directory `/etc/sane.d/dll.d' [dll] sane_init/read_dlld: considering /etc/sane.d/dll.d/iscan [dll] sane_init/read_config: reading dll.d/iscan [dll] add_backend: adding backend `epkowa' [dll] sane_init/read_dlld: done. [dll] sane_init/read_config: reading dll.conf [dll] add_backend: adding backend `net' [dll] add_backend: adding backend `abaton' [dll] add_backend: adding backend `agfafocus' [dll] add_backend: adding backend `apple' [dll] add_backend: adding backend `avision' [dll] add_backend: adding backend `artec' [dll] add_backend: adding backend `artec_eplus48u' [dll] add_backend: adding backend `as6e' [dll] add_backend: adding backend `bh' [dll] add_backend: adding backend `canon' [dll] add_backend: adding backend `canon630u' [dll] add_backend: adding backend `canon_dr' [dll] add_backend: adding backend `cardscan' [dll] add_backend: adding backend `coolscan' [dll] add_backend: adding backend `coolscan3' [dll] add_backend: adding backend `dell1600n_net' [dll] add_backend: adding backend `dmc' [dll] add_backend: adding backend `epkowa' [dll] add_backend: `epkowa' is already there -------------- snip ---------------- -------------- plenty of lines here, no brother backend though; backends are listed in aphabetical order, copy-pasted the text up to 'epkowa', which is the Epson Perfection 4490 Photo scanner (unplugged), since it is one of the scanners that do not work without tinkering with the backend location [dll] sane_get_devices -------------- snip ---------------- -------------- plenty of text here too, no brother backend found and loaded, I include the Epson Perfection lines [dll] load: searching backend `epkowa' in `/usr/lib/x86_64-linux-gnu/sane' [dll] load: trying to load `/usr/lib/x86_64-linux-gnu/sane/libsane-epkowa.so.1' [dll] load: dlopen()ing `/usr/lib/x86_64-linux-gnu/sane/libsane-epkowa.so.1' [dll] init: initializing backend `epkowa' [dll] init: backend `epkowa' is version 1.0.213 -------------- snip ---------------- [dll] sane_get_devices: found 0 devices No scanners were identified. If you were expecting something different, check that the scanner is plugged in, turned on and detected by the sane-find-scanner tool (if appropriate). Please read the documentation which came with this software (README, FAQ, manpages). [dll] sane_exit: exiting [dll] sane_exit: calling backend `xerox_mfp's exit function -------------- snip ---------------- -------------- plenty of text again, no brother backend, I include the Epson Perfection lines. It's in reverse alphabetical order, except for the net backend [dll] sane_exit: calling backend `epkowa's exit function [dll] sane_exit: calling backend `dmc's exit function [dll] sane_exit: calling backend `dell1600n_net's exit function [dll] sane_exit: calling backend `coolscan3's exit function [dll] sane_exit: calling backend `coolscan's exit function [dll] sane_exit: calling backend `cardscan's exit function [dll] sane_exit: calling backend `canon_dr's exit function [dll] sane_exit: calling backend `canon630u's exit function [dll] sane_exit: calling backend `canon's exit function [dll] sane_exit: calling backend `bh's exit function [dll] sane_exit: calling backend `artec_eplus48u's exit function [dll] sane_exit: calling backend `artec's exit function [dll] sane_exit: calling backend `avision's exit function [dll] sane_exit: calling backend `apple's exit function [dll] sane_exit: calling backend `agfafocus's exit function [dll] sane_exit: calling backend `abaton's exit function [dll] sane_exit: calling backend `net's exit function [dll] sane_exit: finished 'xsane' does not see the scanner; and now 'sudo sane-find-scanner' -------------- snip ---------------- found USB scanner (vendor=0x04f9 [Brother], product=0x035d [MFC-1910W]) at libusb:002:006 -------------- snip ---------------- 'sudo scanimage -L' gave no output except the "No scanners were identified" message; I realized debug was off, and ran 'sudo export SANE_DEBUG_DLL=255' which gave "command not found" the following is the output after 'su root', 'SANE_DEBUG_DLL=255', and 'sane-find-scanner' -------------- snip ---------------- found USB scanner (vendor=0x04f9 [Brother], product=0x035d [MFC-1910W]) at libusb:002:006 -------------- snip ---------------- when running 'scanimage -L' as root the outcome is the same as with the regular user: no references to the brother backend and the "No scanners were identified" message and now the 'xsane' command ran as root (soon after the 'scanimage -L' failure) Gtk-Message: Failed to load module "overlay-scrollbar" (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion 'G_IS_DBUS_CONNECTION (connection)' failed (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion 'G_IS_DBUS_CONNECTION (connection)' failed (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_get_unique_name: assertion 'G_IS_DBUS_CONNECTION (connection)' failed [sanei_debug] Setting debug level of dll to 255. [dll] sane_init: SANE dll backend version 1.0.13 from sane-backends 1.0.27 [dll] sane_init/read_dlld: attempting to open directory `./dll.d' [dll] sane_init/read_dlld: attempting to open directory `/etc/sane.d/dll.d' [dll] sane_init/read_dlld: using config directory `/etc/sane.d/dll.d' [dll] sane_init/read_dlld: considering /etc/sane.d/dll.d/iscan [dll] sane_init/read_config: reading dll.d/iscan [dll] add_backend: adding backend `epkowa' [dll] sane_init/read_dlld: done. [dll] sane_init/read_config: reading dll.conf [dll] add_backend: adding backend `net' [dll] add_backend: adding backend `abaton' [dll] add_backend: adding backend `agfafocus' [dll] add_backend: adding backend `apple' [dll] add_backend: adding backend `avision' [dll] add_backend: adding backend `artec' [dll] add_backend: adding backend `artec_eplus48u' [dll] add_backend: adding backend `as6e' [dll] add_backend: adding backend `bh' [dll] add_backend: adding backend `canon' [dll] add_backend: adding backend `canon630u' [dll] add_backend: adding backend `canon_dr' [dll] add_backend: adding backend `cardscan' [dll] add_backend: adding backend `coolscan' [dll] add_backend: adding backend `coolscan3' [dll] add_backend: adding backend `dell1600n_net' [dll] add_backend: adding backend `dmc' [dll] add_backend: adding backend `epjitsu' [dll] add_backend: adding backend `epkowa' -------------- snip ---------------- [dll] add_backend: adding backend `brother4' -------------- snip ---------------- -------------- the brother4 backend is found (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion 'G_IS_DBUS_CONNECTION (connection)' failed (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion 'G_IS_DBUS_CONNECTION (connection)' failed (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_get_unique_name: assertion 'G_IS_DBUS_CONNECTION (connection)' failed [dll] sane_get_devices [dll] load: searching backend `brother4' in `/usr/lib/x86_64-linux-gnu/sane' [dll] load: trying to load `/usr/lib/x86_64-linux-gnu/sane/libsane-brother4.so.1' [dll] load: dlopen()ing `/usr/lib/x86_64-linux-gnu/sane/libsane-brother4.so.1' [dll] init: initializing backend `brother4' [dll] init: backend `brother4' is version 1.0.1 -------------- snip ---------------- [dll] load: searching backend `epkowa' in `/usr/lib/x86_64-linux-gnu/sane' [dll] load: trying to load `/usr/lib/x86_64-linux-gnu/sane/libsane-epkowa.so.1' [dll] load: dlopen()ing `/usr/lib/x86_64-linux-gnu/sane/libsane-epkowa.so.1' [dll] init: initializing backend `epkowa' [dll] init: backend `epkowa' is version 1.0.213 -------------- snip ---------------- [dll] load: searching backend `net' in `/usr/lib/x86_64-linux-gnu/sane' [dll] load: trying to load `/usr/lib/x86_64-linux-gnu/sane/libsane-net.so.1' [dll] load: dlopen()ing `/usr/lib/x86_64-linux-gnu/sane/libsane-net.so.1' [dll] init: initializing backend `net' [dll] init: backend `net' is version 1.0.27 [dll] sane_get_devices: found 2 devices -------------- snip ---------------- -------------- 2 devices found as the brother scanner is configured both as usb and network (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion 'G_IS_DBUS_CONNECTION (connection)' failed (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion 'G_IS_DBUS_CONNECTION (connection)' failed (xsane:6056): GLib-GIO-CRITICAL **: g_dbus_connection_get_unique_name: assertion 'G_IS_DBUS_CONNECTION (connection)' failed [dll] sane_exit: exiting [dll] sane_exit: calling backend `brother4's exit function -------------- snip ---------------- [dll] sane_exit: calling backend `epkowa's exit function [dll] sane_exit: calling backend `epjitsu's exit function [dll] sane_exit: calling backend `dmc's exit function [dll] sane_exit: calling backend `dell1600n_net's exit function [dll] sane_exit: calling backend `coolscan3's exit function [dll] sane_exit: calling backend `coolscan's exit function [dll] sane_exit: calling backend `cardscan's exit function [dll] sane_exit: calling backend `canon_dr's exit function [dll] sane_exit: calling backend `canon630u's exit function [dll] sane_exit: calling backend `canon's exit function [dll] sane_exit: calling backend `bh's exit function [dll] sane_exit: calling backend `artec_eplus48u's exit function [dll] sane_exit: calling backend `artec's exit function [dll] sane_exit: calling backend `avision's exit function [dll] sane_exit: calling backend `apple's exit function [dll] sane_exit: calling backend `agfafocus's exit function [dll] sane_exit: calling backend `abaton's exit function [dll] sane_exit: calling backend `net's exit function [dll] sane_exit: finished when the xsane GUI pops up I'm given the choice to either run the usb Brother scanner or the network one, whichever I choose they both work fine; weirdness one: simple-scan and gscan2pdf do not find the scanner even as root; weirdness two: sudo xsane does not work.