Shared mail box delegation control

   Akbar-Shared Mailbox Issue:

Please check below settings first, using Out of the box options:

• Go to https://admin.exchange.microsoft.com (Exchange Admin Center).
• Go to Recipients > Shared.
• Click on the shared mailbox.
• Select Mailbox delegation.
• Under Sent items, check:

• ✅ Copy items sent as this mailbox
• ✅ Copy items sent on behalf of this mailbox

  Click Save.

 

or

Using PowerShell script

Get-Mailbox "m365support_group@IMECH544.onmicrosoft.com"| Select-Object MessageCopyForSentAsEnabled, MessageCopyForSendOnBehalfEnabled

Set-Mailbox "m365support_group@IMECH544.onmicrosoft.com" -MessageCopyForSentAsEnabled $true -MessageCopyForSendOnBehalfEnabled $true

 Next Steps:

Run the Set-Mailbox command as above (you’ve already done this).

Ask the user to restart Outlook (or sign out/sign in to Outlook on the web).

Send a test email from the shared mailbox.

Check if a copy appears in the shared mailbox’s Sent Items.