SUMMARY I am trying to add a Brother MFC-L2750DW over the network, which had previously worked, but since a recent update, jobs were failing, and after reinstalling Neon from an up-to-date ISO, I now cannot add the printer at all. I have tried manually adding it with lpadmin, upon which it got added with a raw printer driver, but attempting to change the driver to the correct one from systemsettings resulted in an error: "Invalid argument." STEPS TO REPRODUCE 1. Have a Brother MFC-L2750DW on the same network as the KDE Neon system (not connected via USB). 2. Attempt to add the printer via System Settings -> Printers. OBSERVED RESULT The printer will be discovered, and the correct driver selected, but upon clicking "Finish," no printer is added. EXPECTED RESULT The printer is added and is usable. SOFTWARE/OS VERSIONS Windows: No macOS: No Linux/KDE Plasma: KDE Neon 5.25 user edition (available in About System) KDE Plasma Version: 5.25.5 KDE Frameworks Version: 5.98.0 Qt Version: 5.15.6 ADDITIONAL INFORMATION The official Brother driver packages resulted in a printer being added, but when i tried to print, it's status changed to: Idle - "Unable to locate printer."
Can you try this with Plasma6?
I have since abandoned Neon for Fedora, and Plasma 6 is not released for that yet. However, network scanning was recently failing, until I checked and saw that the printer was telling me I might need to reconfigure my firewall. I allowed the ports through the firewall that Brother recommended upon searching online for them, and now scanning works. I didn’t try adding the printer over the network on this distro recently, but it worked when I tried it just now.
It should be fine when/if you get to Plasma6, so I'm going to resolve this. If you have any trouble don't hesitate to open an issue.