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https://deploymentbunny.com/2017/04/25/nice-to-know-after-in-place-upgrade-of-windows-server-2012-r2-to-windows-server-2016-with-wsus-install-post-install-might-fail/
Nice to Know - After in place upgrade of Windows Server 2012 R2 to Windows Server 2016 with WSUS install, Post Install might fail