10.4.1
This solution has appeared to work for others also so I have hope that it still will for me. Thanks for your replies.
Are you in a multi-server environment?
Did you reboot server so changes would take affect?
No single server. I did not reboot the entire server but I did shut down and restart Arcgis Server services - like the article mentions. I'm not the IT guy just the GIS guy - I can ask the IT guy to schedule a server reboot over the weekend to see if that works.
Has anyone ever seen this solution revert to the problematic output after it has been fixed for some time using the 40538 KB article solution?
Only if the maps output is somehow larger then the ArcGIS Servers default printer is capable of.
That is not what occurred. I set the default printer to be larger than any pdf that my orgs web apps produce and it was working as expected for at least 6 months. I have not used the print functionality myself in months and I was surprised to see the issue appear again.
And you checked to make sure it is still the default printer?
It is still the default printer but the page size which I set to "Arch E" was now the default "Letter" size.
Can you think of anything that would cause a printer preference such as this to revert back to default?
Could be something as a windows update updating the driver used for that device.
I spoke to IT personnel who handle the Windows Server servers and there have been no changes including windows updates. Unlike the KB article all I needed to do was set the printer preference size back to "Arch E" to solve the problem without having to stop and start the ArcGIS Server service, so it was a completely unobtrusive solution where I did not need to stop all enterprise AGS services. Unfortunately, I still have no idea what caused this reversion in the first place.