SUMMARY I have a Samsung Xpress M2885FW printer, but when I run Skanlite, it always displays the error message "Opening the selected scanner failed". However, xsane finds it and successfully scans. Before Skanlite displays the error message, it very briefly shows some other error message, but it disappears too quickly to be readable. Running Skanlite from the command line doesn't show any error message either. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Debian 12 (bookworm) KDE Plasma Version: 5.27.5 KDE Frameworks Version: 5.103.0 Qt Version: 5.15.8 libsane1 version: 1.2.1
Can you try again with Skanlite 23.08 which was just released?
I run Debian stable, so it's likely to be quite some time before I can try version 23.08 unfortunately.
Ooops I have managed to miss this one... What backend are you using? sane-airscan? or is there also some USB backend? if it is sane-airscan you could start Skanlite with sane debugging enabled I'm not 100% sure about this backend's debugging, but it is usually something like "SANE_DEBUG_<Backend>=[0-255] skanlite" This page probably has more data on debugging: https://manpages.debian.org/testing/sane-airscan/sane-airscan.5.en.html
I've discovered that Skanlite only fails to find my printer on its first run after rebooting (I don't know if logging out and back in would have the same result). On subsequent invocations, it finds the printer OK. However, in the message box which is displayed on the first run which says that no devices have been discovered, if I click on the button to scan for devices again, it still fails to find anything. It's only when I close Skanlite and start it again that it finds the device.
It now seems to work on the first attempt. Skanlite hasn't been updated on my system since my original report, so maybe something else changed which has fixed things?