After trying all of these options with no success –

Add the Shared Mailbox as a separate account to the same Outlook profile.

Optional IT Step

If the mailbox is auto mapped, you may need to remove and re-add the permissions using Exchange Online Powershell with -AutoMapping:$false.

Remove-MailboxPermission SharedMailbox – User – AccessRights FullAccess

Add-MailboxPermission SharedMailbox -User – AccessRights FullAccess -AutoMapping:$false

Next Step

Add the Shared Mailbox to the profile using the Add Account Setup.

Click File > Account Settings > Account Settings… SharedMailbox-AccountSettings

Select New… Enter the email address of the Shared Mailbox into the “Your Name” and “E-mail Address” textbox.  Click Next.


When prompted for credentials, enter the same credentials as the primary Office 365 mailbox owner.


After the email account is successfully configured, restart Outlook.