Shared Printer Problem

I have set up my Canon printer to be shared with my second, routed,
computer.

However, I'm not able to print from my second computer. I receive an
"Error - Sent to Printer" message in my printer queue.

Is it possible that the problem is that I have the wrong ports selected in
both computers.

If that's the problem, how do I find the name or number of the port in my
host computer?

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