I have a Pi 3B+ running Ubuntu Mate 18.04 with all current updates. I attempted to add a network printer (Brother HL5170DN) which is accessible on my LAN. I went through the normal Add a printer drill. I did notice that it seemed VERY SLOW and the system would freeze during the process - no mouse response - but it did eventually allow me to select the printer and driver. I tried Generic Postscript which I use on CentOS 7 machines and the actual Brother driver which I use on Mint machines. So far so good. When I hit the final Apply the Pi worked for a while and then came back with this strange error
CUPS server Error
There was an error during the CUPS operation: 'success'
I am now back at the Apply/Cancel page and if I cancel I find the printer is not installed.
I do not think I have tried to add a printer to a Pi before. I have 3 Pi's in "production" but they do not need print capability. Any suggestions?
TIA,
Ken