Since the 1st of May 2017 the documentation of Windows Server 2016 moved to another location.

From Technet to Docs.microsoft.com

You can find the documentation overhere:

1. Windows Server 2016 documentation at https://docs.microsoft.com/windows-server/windows-server-2016
2. Windows Server 2016 Networking documentation at https://docs.microsoft.com/windows-server/networking/networking

 

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