After tons of searching, misguided efforts from HP "experts" trying to point at the router - I think I found the solution in bvwjm's post.
his/her comment:::
I changed the port address in Printer Properties that Windows was using to find the printer, from the HP network rediscovery port monitor, to my assigned static IP address with port type "Standard TCP/IP Port".
I am finally able to print - no reboot! I will cycle a few times and see how it does for a week, but allowing "printer pooling" and adding the port - matching my IP address on the printer seems to have solidified things.
Re affirms my posts on other errors like this - it is not a router issue as the HP experts point the finger away from HP