Creation of shared mailbox failed (AAD Graph doesn't return correct format for Values member.)

Kat 96 Reputation points


Am getting the following error message when attempting to create a shared mailbox for "":

Creation of shared mailbox failed

An Azure Active Directory call was made to keep object in sync between Azure Active Directory and Exchange Online. However, it failed. Detailed error message: AAD Graph doesn't return correct format for Values member. The AAD Graph error string is: [{"Item":"PropertyName","Value":"proxyAddresses"},{"Item":"PropertyErrorCode","Value":"ObjectConflict"},{"Item":"ConflictingObjects","Value":"Contact_efaae3d7-xxxxxxxxxxf"}] RequestId : f9354866-xxxxxxxxxxf The issue may be transient and please retry a couple of minutes later. If issue persists, please see exception members for more information.

As far as I can tell, has not been used within Microsoft 365 and should be free, in particular no existing users or groups use this email address. I tried a few times yesterday and today, so many minutes apart, and also in powershell, all attempts return the same error message. Furthermore, just fyi, was able to create a different shared mailbox earlier without any issues.

Any input would be greatly appreciated.

Kind Regards!

Exchange Server Management
Exchange Server Management
Exchange Server: A family of Microsoft client/server messaging and collaboration software.Management: The act or process of organizing, handling, directing or controlling something.
7,440 questions
0 comments No comments
{count} votes

2 answers

Sort by: Most helpful
  1. Vasil Michev 98,516 Reputation points MVP

    Just to be on the safe side, run Get-Recipient This is the fastest way to check whether a conflicting object exists.

    1 person found this answer helpful.

  2. KyleXu-MSFT 26,226 Reputation points


    I would suggest you try to check and delete this Contact from GUI, you could find Contacts from those two places:

    Contacts in Microsoft 365 admin center

    Contacts in Exchange online admin center

    If the response is helpful, please click "Accept Answer" and upvote it.
    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.