In Windows Server 2008 R2 and Windows Server 2012, you can lower the Forest and Domain functional level from 2012 to 2008 R2, or from 2008 R2 to 2008. But you cannot lower it beyond 2008. Also, this is not possible by GUI, you have to use PowerShell for doing this. Let’s see how you can do it in the following steps:
1. Import the AD module
Import-Module -Name ActiveDirectory
2. Check the Forest Functional level of your Active Directory
Get-ADForest | Format-Table Name , ForestMode
You can also check it by going to AD Domain and services.
3. Lower the Forest Functional Level and then the Domain Functional Level
Set-ADForestMode –Identity “woodgrovebank.com” –ForestMode Windows2008Forest
Set-ADDomainMode –Identity “woodgrovebank.com” –DomainMode Windows2008Domain
4. To Confirm your Forest Functional level of your Active Directory
The only thing that you want to keep in mind is your recycle bin functionality which should not be enabled. (Its disabled by default).
Hope this helps. Happy reading!
Very interesting. Thanks!
Well written and to the point... keep it up
This does not work.
It worked for me but I had to remove quotation marks from the domain name. I downgraded the Forest and then the Domain from 2012 R2 to 2012, successfully. Thank you.
This process worked for me. Follow the steps explicitly.
Thanks for this.
It worked for me. Thank you.
Is this a support function from Microsoft?
The following article says:
"You can change the domain mode to a mode with higher functionality only."
This worked great for me. Used it to step a server 2012 domain and forest back to server 2008 in order to promote an existing Server 2008 machine to a secondary domain controller. Thanks a ton!
I was easily able to downgrade a Windows 2012 forest and domain to Windows2008R2 in order to promote a slightly older server to DC.
Excellent instructions and easy to follow