SQL Server Error 258

Oddly, I see this happening more often than I'd expect.  I did notice that a PING to the server name came back with the IPv6 address rather than the IPv4 address.   I don't expect that would be the case with everyone, but I have the Windows 2016 Business Essentials setup as my domain controller and it may have been upgraded from previous versions.  I am still getting accustomed to differences.

That said, at this point, there is a continuous Error 258 returned.   I tried changing the hosts file to reflect the IPv4 rather than the IPv6 (which worked), but the timeout still occurs.   I suspect there is an issue with certificates that may be beyond my ability to understand at this point.   I will persist here and discover some other method.

Thus far  tried:

\

,

,\

The SQL Browser is running meaning the first one should have worked since it is all within the domain.  In the calling application D:\Program Files\Microsoft SQL Server\MSSQL14.HALLORAN\MSSQL\Binn\sqlservr.exe is a firewall exception and in the destination server, the port is open in the inbound rules.

I am thinking the remote timeout being too short is nonsense - Ping is 3ms - but I'll try that too.

Different than what the others have here - my database engine service is running on a group Managed Service Account that has domain and SPN capability across three servers running SQL Server Enterprise or Developer - whichever is preferred.   The SPN's will need to be checked.  Possibly that is also the issue.  One of the SPN requirements is to create the SPN only from the server itself (and I keep saying server but these instances are actually running on Windows 10 v1809 machines).

So much to check now.  What happened to those good old days?  When life was so much easier.

R, J