My ScanSnap IX500 stopped working recently, possibly on upgrade from Debian jessie to stretch.Per the documentation in http://www.sane-project.org/man/sane-fujitsu.5.html I set the environmental variable SANE_DEBUG_FUJITSU=5and then ran xsane, I got:fujitsu] sane_init: fujitsu backend 1.0.127, from sane-backends 1.0.25[fujitsu] sane_get_devices: config option buffer-size (262144) is > 65536, warning![fujitsu] stat: return error 'Error during device I/O'[fujitsu] WARNING: Brain-dead scanner. Hitting with stick [fujitsu] stat: return error 'Error during device I/O'[fujitsu] WARNING: Brain-dead scanner. Hitting with stick again[fujitsu] stat: return error 'Error during device I/O'[fujitsu] wait_scanner: error 'Error during device I/O'[fujitsu] connect_fd: could not wait_scannerIt shows up in lsusb as Bus 004 Device 002: ID 04c5:132b Fujitsu, Ltd It shows up intermittently in scanimage -L, but currently it's showing:SANE_DEBUG_FUJITSU=15 scanimage -L[fujitsu] attach_one: start[fujitsu] attach_one: looking for 'libusb:003:015'[fujitsu] connect_fd: start[fujitsu] connect_fd: opening USB device[fujitsu] connect_fd: could not open device: 3[fujitsu] connect_fd: finishWhy is it not working? How do I fix it?Note: the scanner is plugged into a USB 2 slot. I earlier had it plugged into a USB 3 slot. I tried switching it to a USB 2 slot because of some reports that USB 3 was the problem, but it's still not working.See for example the bug reports: https://bugzilla.redhat.com/show_bug.cgi?id=1297169andhttp://sane-devel.alioth.debian.narkive.com/kLQc0Aik/fujitsu-ix500-no-scanners-were-identifiedIn any case, a USB device should work regardless whether it's plugged into a USB 2 or USB 3 slot.Thanks to Anthony (@derobert) for assistance debugging this.It seems likely that sane-backends is the problem, and that downgrading or upgrading it will make the problem go away. stretch is using 1.0.25-4.1, while jessie used 1.0.24-8+deb8u2, and experimental has 1.0.27-1~experimental2.Also, unplugging it and then plugging it back in again seems to make it visible again for awhile. Which suggests the problem may not be with sane-backends and may be a USB issue.
Fujitsu ScanSnap IX500 scanner stopped working, possibly on upgrade from Debian jessie to stretch
debian;sane