step by step instruction on how to add a domain controller to windows server 2025

Question

What if I had demoted the domain controller and want to start fresh. I'm noticing that the domain controller initially created in the new forest was not removed. AD DS still wants me to promote the demoted domain controller. Can I still create a new forest with a different domain name.

Answer 1

Yes, you can create a new Active Directory forest with a different domain name even if the previously demoted domain controller still exists in the system. However, you need to ensure that the metadata associated with the old domain controller is cleaned up properly to avoid conflicts during the new forest creation process.

Here are the general steps you should follow:

1. Clean Up Metadata: Before creating a new forest, you need to remove any leftover metadata from the demoted domain controller. This can be done using the Active Directory Sites and Services tool or through the command line using the ntdsutil tool to remove the domain controller's entries.
   • Open ntdsutil and run the following commands:
     • metadata cleanup
     • connections
     • connect to server <your-server-name>
     • quit
     • select operation target
     • list domains (to find your domain)
     • select domain <domain-number>
     • list sites (to find your site)
     • select site <site-number>
     • list servers in site (to find your server)
     • select server <server-number>
     • remove selected server
     • quit and quit again to exit ntdsutil.
2. Install Active Directory Domain Services (AD DS): After cleaning up the metadata, you can proceed to install AD DS on your server. Use the Server Manager to add the Active Directory Domain Services role.
3. Promote to Domain Controller: During the promotion process, select the option to create a new forest and specify the new domain name you wish to use. Make sure to follow the prompts to configure the necessary settings, such as the forest and domain functional levels.
4. Verify Installation: After the installation is complete, verify that the new domain controller is functioning correctly by checking the Active Directory Users and Computers console and ensuring that the new domain appears as expected.

By following these steps, you should be able to create a new forest with a different domain name without issues related to the previously demoted domain controller.

Answer 2

Hi Arica Brown,

It’s quite common to feel puzzled after demoting a domain controller, only to see AD DS still referencing it. The reason is that the demotion doesn’t always clear every trace — leftover metadata can make AD DS think the old controller is still present.

The good news is you can absolutely start fresh with a new forest and domain name. Just be sure the old controller is fully removed first: confirm the AD DS role is gone in Server Manager, run ntdsutil metadata cleanup to clear any remnants, and check DNS zones and Active Directory Sites and Services for ghost entries.

Once that cleanup is complete, you can safely create a new forest with your chosen domain name and move forward without AD DS prompting you about the old controller.

Let me know how it goes, and if this answer helps, feel free to hit “Accept Answer” so others can benefit too 😊

Domic Vo.

Answer 3

Good morning Arica Brown,

I hope you are doing well.

Have you found the answer useful? If everything is okay, don't forget to share your experience with the issue by accepting the answer. Should you need more information, free free to leave a message. Happy to help! :)

Domic Vo.