I recently bought a new win Server 2008 Std for my home network. My server was not ready at that time so to check the product key I installed the Win server on my older Pc. The key worked but now when my server is ready I can't get this key to work.

I formatted the d:/ (where the win server was installed) on the older Pc, but still my server says its incorrect. Other thing is when i start my old Pc it still gives the option of win server and win Xp. Do (&How) I have to remove this option when I start my old Pc.

Can someone help me to solve this problem?

I did format the whole drive in the old computer!!!

But it didn't work