Site mailboxes are created by using incorrect email addresses

Site mailboxes are created by using an incorrect email address in Office 365. For example, consider the following scenario.
  • You have the following four domains in Office 365:
  • and are accepted domains that were added to the Hybrid Configuration wizard. is federated and can't be set as the default accepted domain in Office 365. Therefore, shows as the default domain.
To resolve this issue, change the email addresses of the site mailbox. To do this, follow these steps:
  1. Connect to Exchange Online by using remote PowerShell. For more information, see Connect to Exchange Online using remote PowerShell.
  2. Run the following command:
    Set-Mailbox -Identity MySiteMailbox1 -EmailAddresses, -EmailAddressPolicyEnabled:$False
Still need help? Go to the Office 365 Community website.

Article ID: 3172620 - Last Review: 08/12/2016 05:38:00 - Revision: 1.0

Microsoft Exchange Online

  • o365e o365m o365022013 o365 o365a KB3172620