.com NETBIOS

Question

.com NETBIOS

Rick 0

We are trying to move to Entra ID but have a .com NETBIOS name with a 2019 Exchange on prem.

Has anyone else experienced this and been able to move forward without creating a new domain?

0 comments

1 answer

Your answer

Answer 1

Elena-VH 1,490 Independent Advisor

Dear @Rick

Yes, it is possible to move forward with Microsoft Entra ID without creating a new domain. The NETBIOS name itself is typically not a blocker for Entra ID integration. What is most important is that users have a routable, verified UPN suffix (for example, username with the domain @company.com) that matches a domain verified in Entra ID. For reference: Microsoft Entra UserPrincipalName population and Plan and troubleshoot UserPrincipalName changes in Microsoft Entra ID

Exchange Server 2019 on-premises can also coexist with Entra ID synchronization and hybrid configurations without requiring a domain rebuild, provided the Active Directory and Exchange environments are healthy and the UPN configuration is aligned with the verified domain in Entra ID.

Before considering a domain migration, it would be helpful to verify:

The Active Directory DNS domain name
The NETBIOS name
The UPN suffix currently assigned to users
Whether that UPN suffix is verified in Entra ID

I hope the information shared is helpful. If you have any questions, please feel free to reach out. I'm looking forward to your update.

If the answer is helpful, please click "Yes" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

Note: Please follow the steps in the documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Rick 0 Reputation points

2026-08-13T21:46:13.5933333+00:00

Hi Elena, Thank you for responding.
In the following article under "On-Premise Active Directory" it states "Using on-premises forests or domains by using "dotted" (name contains a period ".") NetBIOS names isn't supported." We've also been told the same by a few different consultants.
https://learn.microsoft.com/en-us/entra/identity/hybrid/connect/how-to-connect-install-prerequisites
Elena-VH 1,490 Reputation points Independent Advisor

2026-08-14T03:59:18.7133333+00:00

Dear @Rick

Thanks for your helpful information, and I apologize for the confusion in my earlier response. In my initial response, I focused on the DNS/UPN domain naming aspect and overlooked the specific restriction regarding a dotted NETBIOS name.

Moreover, thank you for bringing the documentation to my attention. Based on the Microsoft guidance and the feedback you've received from other consultants, the concern is valid.

Given the documented support limitation and the feedback you've already received from other consultants, I would recommend opening a Microsoft support ticket to discuss your specific environment and migration plans. They can provide the most authoritative guidance on whether there is a supported path forward with your current configuration. For reference: Get support for Microsoft 365 for business or Microsoft Unified Support

Thank you for your patience and understanding. I'm looking forward to your update.
Rick 0 Reputation points

2026-08-14T17:13:41.1933333+00:00

Thank you Elena. I appreciate your help.
Elena-VH 1,490 Reputation points Independent Advisor

2026-08-17T03:26:22.63+00:00

Dear @Rick

You're very welcome! It was my pleasure to assist you. If there's anything else I can help with, please feel free to reach out.