How can I set msExchMailboxGUID attribute to null?




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    Brian Mink

    There are steps missing from this process. I don't know if it is because the tool was updated or the author simply missed them. I suspect the former.

    When you select In from AD – User Exchange, you must then click Edit, and answer a prompt that comes up asking if you want to edit the original, or disable the original and edit a clone. It states that the second option is preferable.

    Finally, when saving the edit, I get a message that "A deadlock occurred in SQL Server while trying to acquire an application lock.,Microsoft.IdentityManagement.PowerShell.Cmdlet.AddADSyncRuleCmdlet".

    While instructions on avoiding that error would be nice, so would the PowerShell command that would allow me to do this more quickly.

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    Patti Domingo

    I am getting the same error. 

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    Rob Latino

    Hi Brian Mink and Patti Domingo,

    Please refer to this article for additional information about setting a filter, using AAD Connect, that will clear the msExchMailboxGuid so that objects can be synchronized between environments:


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    Dyan Brockbank

    Setting the Source msExchMailboxGuid to NULL is not possible in AADConnect version 1.1.649.0. The only options are the ones on the list. Is there a way to somehow add NULL to the list?

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    Rob Latino

    Hi Dyan Brockbank,

    Azure AD Connect is a tool developed by Microsoft. We're unable to add options to that tool. However, we'll evaluate how we can improve this article to better address the issue.

    Microsoft has recently published an excellent article about Azure AD filtering, and we recommend that you follow the instructions in that article instead. Go to the URL listed below to read that article.

    Thank you for your feedback. Let me know if you have further questions.


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    Vanna R

    Why do you set msExchMailboxGuid to Null? Isn't it exchange mandated system attribute?

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    noc infoaxis

    Even though it state this was updated 2 months ago, I have reservations that anyone actually looked to see if there was a new version of the tool.  You cannot set NUL and the program eventually crashes trying to make the changes stated here.

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