Hello @Glenn Maxwell
This might occur if the Software Licensing service is not started. Start the Software Licensing service and check if that helps you.
-Click Start, type services.msc and hit enter.
-In the list of services locate Software Licensing.
-Right-click it, select Properties.
-Change “Startup type:” to Automatic, then click OK.
-You may then need to select Software Licensing again then click “Restart the service” located in the top-left corner for it to take effect immediately.
-Restart the server and then try activating the License on your windows 2016 server.
Hope this resolves your Query!!
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