Personally I'm not fond of printers shared from a computer and prefer them to be on the network.
Same here, but if you don't have a wireless printer and you don't have a router that's good about direct connect support (and very many aren't) then you're only left with one option.
What you proposed as far as "\\ComputerA\Printer" is precisely what I was presuming would be found in the networking information on the computer that was functioning with the printer on Computer A and that could be manually entered in the "Add Network Printer" setup by hand on the one that was not. I don't know why Windows 7 was, and remains, so flaky with regard to this.
Brian AKA Bri the Tech Guy (my website address is in my profile) Windows 10 Home, 64-bit, Version 1709, Build 16299
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