Send mail as a shared mailbox

Question

I'm trying to set up the sending of mail as if it is coming from a shared mailbox.

I've added the appropriate permissions, and each time I send a message I get the following error message:

This message could not be sent. You do not have the permission to send the message on behalf of the specified user.

__________________________________________________

Diagnostic information for administrators:

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Error is [0x80070005-0x000004dc-0x00000524].

Exchange response headers:

request-id: ffb587f8-b34b-4a07-9932-f2b75c2bcaf9

X-ServerApplication: Exchange/15.20.0631.016

X-FEServer: YTXPR0101CA0029

X-BEServer: DM3PR17MB0620

X-CalculatedBETarget: DM3PR17MB0620.namprd17.prod.outlook.com

X-RequestId: {D090B0F4-C5D9-482C-9A2C-8F034D718473}:68

X-ClientInfo: {F25B317F-7E5C-4014-9890-50055300A1D4}:5800031

X-ElapsedTime: 109

X-BackEndHttpStatus: 200

X-ResponseCode: 0

X-DiagInfo: DM3PR17MB0620

X-RequestType: Execute

I've tried to also send the message using the Outlook Web App. I've been able to add the shared folder to access the emails from the shared mailbox into the account, however the email address of the shared mailbox is not one of the options when I go to select "From" to change the message coming from my account rather than the shared account.

If someone could please point me in the right direction, I'd really appreciate it.

Thanks.

Peace & Blessings,

Colin+

Answer 1

Hello Colin,

What permission did you assign? From the error message, it seems that you only assigned the Full Access permission, so you can add the shared mailbox to your account and view the emails, but you are not able to send the emails as the shared mailbox.

Please sign in Office 365 and go to Exchange Admin Center(EAC)->recipients->shared, click and edit the shared mailbox. Then go to mailbox delegation, add your account to the Sent As permission list. Then wait a few hours to take effect. Then you will be able to send emails as the shared mailbox. In Outlook 2016 client, click From and choose Other Email Address and type the address of the shared mailbox.

Regards,

Rick

Answer 2

Hello Colin,

From the screenshot in private message, we can confirm that you have add your account the “Full Access” and “Send As” permission to the shared mailbox. I suggest you follow the instructions below to send emails as the shared mailbox:

In Outlook Web App(OWA):

1 . Sign in OWA and on the OWA navigation bar, click your name, click Open another mailbox.

2 . Type the email address of the shared mailbox, click Open.

3 . Then it will open the shared mailbox in a separate browser window. Then you can send emails using the shared mailbox.

 

In Outlook 2016 client:

1 . After you have the correct permission of the shared mailbox, the shared mailbox will be shown automatically under your account.

2 . Click new email and click the From.

3 . Choose Other Email Address and then type the address of the shared mailbox. Then you will be able to send emails from the shared mailbox.

 

If you still can not send the emails using the shared mailbox, please capture a screen of the new error message for further check.

Regards,

Rick

Answer 3

Hello Colin,

Sorry for the late reply as I was off-duty before.

You can try to remove and re-add your account, and wait a few hours to see if it takes effects. Besides, you can also manage the permission in Office 365 Admin Center->Groups->Shared mailboxes, then click and edit the shared mailbox, click Customize permissions.

If the issue persists, please follow the instructions below to add send as permission using PowerShell:

1 . Connect to Exchange Online PowerShell.

2 . Run the following cmds: Add-RecipientPermission -Identity @domain.com -AccessRights SendAs -Trustee “@domain.com”

It will add ******@domain.com send as permission of the shared mailbox. If the issue persists after you added it using PowerShell, please capture a full screenshot of the new error message. And then run the following cmds:

1 . ***Get-MailboxPermission -Identity ***@domain.com

2 . Get-RecipientPermission -Identity ****

Then paste the full results via private message for further check. Please also let me know which mailbox is your account. To protect your privacy, I have sent you a private message to collect them. Please click on the link below to access your Private Message : https://answers.microsoft.com/en-us/privatemessage/inbox

Regards,

Rick

Answer 4

Hi Rick,

It works in OWA, but not Outlook 2016. I've sent another private message with the details.

Peace & Blessings,

Colin+

Answer 5

Hi Rick,

This is what I saw when I followed your instructions:

To me, it looks like the Send As permission is already set. Should I delete the permissions and re-add them?

Peace & Blessings,

Colin+

[PII removed by Rick Song MSFT, 6:58 AM, April 8, 2018(UTC)]