NEC Express5800 User Manual page 471

For a server running a Server Core installation
1.
At the command prompt, type slmgr –dli, and press Enter.
IMPORTANT:
already been activated on your system. Click
2.
Type slmgr –ipk <PID>, and press Enter.
* PID is your product key on the COA label.
3.
Type slmgr –dti to obtain an installation ID for Windows activation, and press Enter.
4.
See "%systemroot%\system32\sppui\phone.inf" for the phone number of the Microsoft
customer service.
If the following message appears, Windows has
Installing Windows Server 2008 R2 D-25
to exit.