As I've found now the origin of '/etc/udev/rules.d/79-udev-epson.rules' - it was installed by the epson-printer-utility for my Epson XP 540 - I tried what happens when I switch to a more 'common' udev rule.
I tried (similiar to the rule for brother scanners provided by Hans): ATTRS{idVendor}=="04b8", ATTRS{idProduct}=="*", MODE="0664", GROUP="scanner", ENV{libsane_matched}="yes" Result: No firmware up-load, no scanner found. As soon as a I switch back to the rule installed by epson the scanner starts (after switching off-on) to up-load the firmware and is accessible by scanning programs (as non-root). @luca can you please try the following udev rule (scanner is locally attached via usb, please keep the current one stored at an other place, no garantuee, so you may want to revert) : /etc/udev/rules.d/79-udev-brother.rules # chmod device BROTHER group ATTRS{manufacturer}=="BROTHER", DRIVERS=="usb", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f9", ATTRS{idProduct}=="*", MODE="0777" -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to sane-backends in Ubuntu. https://bugs.launchpad.net/bugs/1728012 Title: Many 3rd party scanner drivers are broken by a sane change Status in sane-backends package in Ubuntu: Confirmed Bug description: Many scanners can no more be used since sane has changed something: The 3rd-party plug-in the vendor provides as .deb package will still install. But the scanner is no more recognized. Scanners that are affected are(besides others): - Epson Perfection V10 - Epson Perfection V1000 - Epson WorkForce GT-1500 - Brother MFC-8510DN - Epson Perfection V33 It is to note that the probability that the scanner manufacturers fix things others broke is below 100%. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: libsane1 1.0.27-1~experimental2ubuntu2 Uname: Linux 4.14.0-041400rc5-lowlatency x86_64 ApportVersion: 2.20.7-0ubuntu3.1 Architecture: amd64 Date: Fri Oct 27 12:35:52 2017 EcryptfsInUse: Yes SourcePackage: sane-backends UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/sane-backends/+bug/1728012/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp