Server2019 can not be promoted to DC in an existing Server2008 domain

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"

BONUS INFO:
Originally this WAS a Server2000 domain which was upgraded more than 10 years ago.
OhmitAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Shreedhar EtteTechnical ManagerCommented:
Ohmit,

Please execute the below command on domain controller in powershell to valid the forest functional level.
Get-ADForest | fl Name,ForestMode

Is it a single domain controller environment?

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Cliff GaliherCommented:
Forest and domain functional levels are not raised when you install new domain controllers. So you can have 2008 DCs and still be at a 2000 functional level.  You'll need to raise the functional levels to the minimum required level.
OhmitAuthor Commented:
Thanks guys. Ill get back to you as soon as possible :-)
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows Server 2019

From novice to tech pro — start learning today.