Tonight I’m trying to promote a spanking new Windows 2008 R2 server as a domain controller in an existing Windows 2003 AD. When I ran dcpromo on the new server I was presented with the following message from the Active Directory Domain Services Installation Wizard, “To install a domain controller into this Active Directory forest, you must first prepare the forest using “adprep /forestprep”. The Adprep utility is available on the Windows Server 2008 R2 installation media in the supportadprep folder.”
I promptly opened and Command Prompt on the R2 server, navigated to the supportadprep folder and ran adprep /forestprep. No joy! Now I got the message:
Adprep cannot run on this platform because it is not an Active Directory Domain Controller.
Adprep stopped without making any changes.
Run Adprep on a Active Directory Domain Controller.
So, I went to one of my 2003 domain controllers and ran adprep /forestprep. Another problem!
The image file C:supportadprepadprep.exe is valid, but is for a machine type other than the current machine.
Before running adprep, all Windows 2000 Active Directory Domain Controllers in the forest should be upgraded to Windows 2000 Service Pack 4 (SP4) or later.
If ALL your existing Windows 2000 Active Directory Domain Controllers meet this requirement, type C and then press ENTER to continue. Otherwise, type any other key and press ENTER to quit.
Just a little bit more….
From the same 2003 server you’ll have to run adprep32 /domainprep as well.
Now that adprep(32) /forestprep and adprep(32) /domainprep were successfull I can promote my 2008 R2 server to DC.