I am a newbie to ubuntu so perhaps I'm missing something. I have a Canon MX452 wireless printer on my home network. I recently installed ubuntu 16.10 on an old laptop, it works great now. I added my printer, which ubuntu identifies as being on the network. However when I try to print, the Printer State goes from idle to processing job, it reaches 15% and then says "unable to locate printer". At the bottom of the printer dialog box it says connected to localhost. I can print using another laptop with Windows loaded. Any suggestions as to what I need to do? Thanks
I just ran into a similar situation, on my Ubuntu 16.04 machine, where I tried to print something and it didn't print. And when I opened the Printer settings, it showed an error message "unable to locate printer", or something to that effect.
Under Printer->Settings, it looked my "Device URI" was set to some bizarre value. I clicked on the Change button, selected "Network Printer" and after a couple seconds my printer showed up in the list of Network Printers, so I selected it and then clicked on the 'Apply' button.
Within seconds, the print request I had previously issued then printed automatically.
BTW, after the above steps, my correct (working) "Device URI" looked like: socket://192.168.0.211:9100
Before, instead of a numerical IP, it had some kind of weird string there.
One possibility as to what might be happening is that sometimes, when Ubuntu checks for the printer via WiFi, the wifi connection may not always go through, in which case Ubuntu inadvertently changes the printer's "Device URI" to something that makes it unusable.
Just a theory based on what I just observed 10 minutes ago.