Shared mailboxes are often used when several people should have access to a mailbox, for example to work together in a team.
However, there are a few things to bear in mind, so this article describes how to set it up and how it works.
The following example shows how to set up a shared mailbox:
The mailboxes specified under "User (blue box)" have full access to the shared mailbox. This can be checked with the following command:
Get-MailboxPermission team | where {$_.AccessRights -contains "FullAccess"}
A user is automatically created in the Active Directory for the shared mailbox. The user account is deactivated by default:
To enable users to access the shared mailbox, it is integrated into Outlook via Autodiscover. The Active Directory attribute "msExchDelegateListLink" is filled with the Distinguished Name (DN) of the user accessing the shared mailbox so that an additional mailbox is distributed via Autodiscover:
Here again in detail, the DN of user Frank is entered in the attribute "msExchDelegateListLink" of the shared mailbox "Team":
Outlook checks cyclically whether there is new Autodiscover information. After a short time, Outlook will include the shared mailbox as an additional mailbox as it receives the necessary information via Autodiscover:
As the corresponding user has full access to the shared mailbox, they can now perform any actions in the mailbox:
However, there are a few things to bear in mind here:
If a user deletes mails from the shared mailbox, the mails are moved to the user's "Deleted items" folder in the default setting, meaning that mails cannot be restored by other users of the shared mailbox.
However, this behavior can be changed. To ensure that deleted items from the shared mailbox also end up in the Deleted items folder of the shared mailbox, a registry key must be set for Outlook:
Windows Registry Editor Version 5.00 [HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Options\General] "DelegateWastebasketStyle"=dword:00000004
The General key and the DWORD DelegateWastebasketStyle must be created. Unfortunately, this usually causes problems: If the user logs on to another computer and does not have a roaming profile, this setting does not take effect. It is therefore best to set this setting via group policy:
For computers outside the Active Directory, a suitable distribution method must be considered. Once the setting has been made, deleted mails will end up in the designated folder:
"Send-as" users also receive rights for the shared mailbox:
There is also a similar stumbling block here as with the deleted items. Mails that are sent in the name or on behalf of the shared mailbox only load in the "Sent items" folder of the user who wrote the mail, but not in the Sent items folder of the shared mailbox. However, this behavior can be changed with less effort:
Set-Mailbox Team -MessageCopyForSentAsEnabled $true -MessageCopyForSendOnBehalfEnabled $true
This means that mails in the name and on behalf of the shared mailbox also end up in the Sent Items folder of the shared mailbox. However, as the name of the parameters suggests, these items are displayed both in the Sent Items folder of the shared mailbox and in the user mailbox (copy).