Hi,
Thanks for your post.
Is it a fresh installation Server?
Did you use the activation key below?
"Upon installation, you will be prompted to activate. Windows Server 2016 Technical Preview 5 will require a product key:
Standard Key: MFY9F-XBN2F-TYFMP-CCV49-RMYVH
Datacenter Key: 6XBNX-4JQGW-QX6QG-74P76-72V67"
Have you tried reboot the server and activate?
Best Regards,
Alivn Wang
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