we had a server running windows server 2008 Foundation that needed to be upgraded to 2008 Standard. i read that for the upgrade to work the server had to be demoted from DC then promoted again after the successful upgrade. the Demote seemed to go fine (no FSMO roles on the server all on the other DC) no errors.
however, after the successful upgrade, i cannot promote it back to DC again, it fails with the following error:
The Operation Failed because:
Active Directory Domain Services could not create the NTDS settings object for this Active Directory Domain Controller CN=NTDS Settings,CN=[servername],CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configurations,DC=[domainname],DC=com on the remote AD DC [otherDC]@[domainname].com. Ensure the provided network credentials have sufficient permissions.
"the RPC server is unavailable"
i have tried using the NTDSUTIL to do a metadata cleanup but there is no record of this server on there so i could not do that/it did not need doing.
any ideas why this is happening?