Joe: Last month we had a 016-781 but that's because someone had accidently yanked the network cable with their foot. Plugging the Xerox back into the network resolved that issue. we have not received any other error besides 016-782 in the past few weeks. If it's a login failure, might that be due to the fact that our server also handled active directory hosting services? I provided the local credentials but it didn't make a difference. All six workstations run Windows 7 and all four laptops run Windows 10. We haven't tried testing scanning on the Windows 10 devices since they aren't used by those staff members who need access to scan functionality.
I actually wrote my original post while I was on hold to talk to a technical support person. They verified my hypothesis by indicating it might be possible to initiate a scan on demand from a workstation, but it would not be possible to send outbound scans from the Xerox without a DNS server. Of course that was tier 1 support. We don't have access to anything more. If you have some insights they do not, I would be eager to learn more.