Merge two account with AzureAD Connect

adam900331 361 Reputation points


I have two domain:

  • Adomain.local
  • has many users and a Hybrid Exchange environment. The public domain is for example The productive domain is Adomain.local, and it has the same user like I synchronized the users with AzureAD Connect what is in the The long-term plan is to migrate all user from to Office365, point MX record to cloud, uninstall on-premise Exchange, decomission The productive domain will be the Adomain.local.

How can I merge the AzureAD user (which synced from the with Adomain.local users and objects? Is there any solution for it?


Microsoft Exchange Hybrid Management
Microsoft Exchange Hybrid Management
Microsoft Exchange: Microsoft messaging and collaboration software.Hybrid Management: Organizing, handling, directing or controlling hybrid deployments.
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Microsoft Entra
Microsoft Entra ID
Microsoft Entra ID
A Microsoft Entra identity service that provides identity management and access control capabilities. Replaces Azure Active Directory.
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  1. KyleXu-MSFT 26,211 Reputation points


    First “.local” isn't supported for publish, you need to change it to ".com".

    Then, if you want to merge them into one, you need to use a unified domain name for them before creating AAD Connect, such as "" for both of them. For local AD, you could add a new accepted domain(from local Exchange) and lookup zone(from local AD) to change it from "Adomain.local" to "", you also need to buy DNS record for it.

    After using a unified domain name for them, you will could use SMTP matching to connect them: How to merge an Office 365 account with an on-premises AD account after hybrid configuration?

    Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

    If there also exist mailbox for local AD, you cannot keep both local mailbox and Exchange online mailbox, you can only keep one for them. You can only merge the AD account without merge mailbox.

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    1 person found this answer helpful.