We've been struggling for the pas few days in trying to find how to add a default signature to a shared mailbox.
The user has a personal mailbox and a shared mailbox which is added automatically when the person has full access rights.
However, we now try to add a signature for the shared mailbox specifically but we're unable to get the mailbox in the list with available e-mail accounts.
1 Answer
According to my experience, only the mailbox that configured mannually in your Outlook would be in the account list to set signature, and the auto-mapped shared mailbox would work with your primary maibox's signature.
In this case, if you need to set up a separate signaure for the shared mailbox, as a workaround, you could try to configure it in Outlook if it has a password.
If you don't like to configure it in Outlook, there may be other workarounds(such as add disclaimers on the server), for more information, please refer to this article:
How to set up different email signatures for a shared mailbox and user mailbox in Office 365?
