To change the serial number on your Windows Server 2008 Core Installation, run “slmgr /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX” where X is your new serial number.
Wait for the popup confirmation message that the serial number has been changed:
Run “cscript c:\windows\system32\slmgr.vbs -ato” to activate the operating system:
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