Forwarding for Entra ID users without licenses

Alex Rough 0 Reputation points
2024-02-07T16:00:54.8166667+00:00

I have a contoso.com domain registered as an Accepted Domain in Exchange Online. I also have bunch of users in Entra ID (formally AAD) registered with their respective contoso.com UPN. I need to set up redirection for those users, so if someone sends an email to John.Miller@contoso.com, a user would get it to his real email address (i.e. john.miller@corpo.com - located in another tenant). I tried to create a mail user with the existing UPN address, but got a message saying

"Mail user creation failed!
The proxy address "SMTP:john.miller@contoso.com" is already being used by the proxy addresses or LegacyExchangeDN. Please choose another proxy address."

I didn't find the way I can remove proxy address from the user. I thought I can use a shared mailbox to create a redirection, but in that case I need to disable the actual users, which is not suitable in my case as they have been used for third party apps. Is there any other way I can set up redirection?

Microsoft Exchange Online
Microsoft Exchange Online Management
Microsoft Exchange Online Management
Microsoft Exchange Online: A Microsoft email and calendaring hosted service.Management: The act or process of organizing, handling, directing or controlling something.
4,060 questions
0 comments No comments
{count} votes

3 answers

Sort by: Most helpful
  1. Kael Yao-MSFT 36,911 Reputation points Microsoft Vendor
    2024-02-08T03:05:12.38+00:00

    Hi @Alex Rough

    What is the current user type of this user John.Miller@contoso.com?

    You can use the following cmdlet in Exchange Online Powershell to check:

    Get-Recipient -identity John.Miller@contoso.com | fl RecipientTypeDetails
    

    If it is usermailbox, you can either create a mail flow rule (Exchange/server side method) or an Outlook inbox rule (Outlook/client side method) to redirect the message to john.miller@corpo.com.


    Mail flow rule: 01

    Outlook inbox rule: 01


    If it is not a usermailbox, the mail flow rule method should still work for you in this case.


    If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".  Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.


  2. Alex Rough 0 Reputation points
    2024-02-08T12:58:41.4866667+00:00

    I found a solution. I just create a shared mailbox and setup forwarding there.

    0 comments No comments

  3. Kael Yao-MSFT 36,911 Reputation points Microsoft Vendor
    2024-02-09T02:09:38.3033333+00:00

    Hi @Alex Rough

    Glad to hear you have found a solution.

    While since Microsoft Q&A forum has a policy that "The question author cannot accept their own answer. They can only accept answers by others", I'll repost your solution in case you'd like to "Accept" the answer : )

    [Forwarding for Entra ID users without licenses]

    Scenario:

    Need to setup email forwarding from John.Miller@contoso.com (current tenant) to John.Miller@corpo.com (external tenant) when John.Miller@contoso.com does not have a mailbox.

    Solution:

    Create shared mailboxes with the email address and setup forwarding on the shared mailboxes.

    0 comments No comments