I'm posting this just incase anyone else falls into this trap...
Summary:
Waste ink cartridge was reported as almost full with a yellow triangle warning on both the printer and in the Mac driver software.
Any print job sent from a Mac never printed; the printer gave no indication that it received anything and there where no errors reported on the printer or in the driver.
All print jobs sent from a Windows 10 system printed just fine.
I have three Mac's, two using version Mac OS 10.14.5 and one using 10.14.4. The printer has the latest firmware 2.070. All use the latest Canon driver software.
The Windows 10 system had the latest Canon driver software too.
After wasting several hours and trying different computers, resetting the Mac print system, reloading drivers etc I changed the MC-20 waste ink cartridge. The Mac computers now print just fine. Grrrr
So, if your Mac stops printing, but doesn't give any errors and the waste ink cartridge is getting full, but not yet reported as full, consider changing it. It looks like the Windows driver correctly distinguishes between almost full and full whereas the Mac driver thinks nearly full equals full. That's my take-away anyway :-(
Kind Regards,
Andy
