Extend Windows Server Evaluation

Windows Server evaluation versions will by default “deactivate” after 180 days.  To extend this period up to 6 times, launch an elevated command prompt and enter the following command.

slmgr – dlv

After a few seconds, a pop-up window should appear displaying information about the licensing status of the server.

https://www.petri.com/how-to-extend-windows-server-evaluation