Shared Mailbox issue

Question

I am not able to send email on behalf of a shared mailbox even if it is configured correctly.

Answer 1

Hi Mark Alvin Diaz, 

Thank you for posting your question in the Microsoft Q&A forum. 

We understand that you're currently unable to send emails on behalf of a shared mailbox, despite having the correct settings in place. To better understand the root cause of the issue and provide more targeted assistance, could you please provide a screenshot of the shared mailbox delegation settings as configured in the Exchange Admin Center (EAC)? Additionally, a screenshot of the Non-Delivery Report (NDR) or bounce-back message you receive when attempting to send from the shared mailbox would be very helpful in diagnosing the problem. 

Could you also confirm whether this issue occurs in both the Outlook desktop application and Outlook on the web (OWA)? 

We look forward to your response and assisting you further. 

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