My Brother HL-5370DW acts connected when I print from my Linux box and a Win 10 box. A second, Win 7 box, can see the printer, and jobs from it queue up, but the status ends with “Not Connected”.
These files begin (as expected) with “smb…”. While they’re unable to print, I can print from the Win 10 box without a problem. I seem to have Schroedinger’s Printer: it is/isn’t connected?