This Copy of Windows is Not Genuine – Windows 2008 Server.
Rearm Extend Windows 2008 Server
Extend the evaluation/grace period without violating EULA. Run the rearm command from a an elevated command prompt and extend the evaluation grace period for windows 2008 Server. As shown in the image, in this post. the command is simple at effective. It takes affect immediately.
Start an Elevated command prompt and then enter “slmgr -rearm” without the quotes.
The command completes in second and removes the following from the desktop. This is particularly useful when testing or demoing Citrix XenApp, XenDesktop or Virtual Desktops including RDS desktops.