I'm managing a Windows domain with 2 server 2008 domain controllers. I need to add a new domain controller running Server 2019. However it is not possible to promote this because I need to raise domain functional level. The strange thing is, that Server2019 tells me, that I need to raise level to at least Server2008 which it is already??
This is the exact error message from the Server2019:
"Verification of replica failed. The forrest functional level is not supported. To install a Windows Server 2019 domain or domain controller, the forrest functional level must be Windows Server 2008 or higher"
Originally this WAS a Server2000 domain which was upgraded more than 10 years ago.