NEC Express5800/120Rh-2 N8100-1126F - Manual (Page 383)

Installing Windows Server 2003 E-21
About Windows Activation
Windows Server 2003 must be activated before you can use Windows Server 2003.
Windows activation process is as follows.
NOTE: When you use Windows Server 2003 R2, activation process is
not needed.
1. Click [Run] on [Start] menu.
Type as follows in the [Open:] box, and click [OK].
oobe/msoobe /a
2. When the screen as follows is displayed, click [Next].