I have a 2003 domain controller and now a new 2008 server. I'm trying to create a 2008 domain controller in my existing forest. I know I have to run adprep. However, it's not letting me run forest prep? If I run on 2008 server it tells me Can't run on this platform because it's no an AD domain controller. If I try to run on 2003 it tells me it's not vaild on this machine? How do I accomplish this? I have a 2008 r2 64 bit server and a 2003 32 bit server?