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Most shared mailboxes are set to “automap” which means the mailbox will automatically appear within beneath main mailbox in Outlook. In this example “itservicedesk” is a shared mailbox.
In some instances, accounts are not set to automap; this is often the case when the shared mailbox is exceedingly large and would slow Outlook down for daily use. To access non-automapped shared mailboxes:
Right-click on folders in the left pane in Outlook, then select “Add shared folder or mailbox”
In the “Add shared folder or mailbox” pane that appears, enter the displayname or email address of the shared mailbox, then click Add
The shared mailbox will now appear beneath your other mail folders.
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Click on the settings gear icon in the top right of the screen
Click “Mail” in the left pane, then “Compose and reply” in the middle section, then in the right-hand panel, click “Always show From” and then click “Save”
The Settings window does not automatically close when the “Save” button is clicked, so click the X in the top right to close the Settings window.
When composing an email, select the appropriate shared mailbox rather than your personal mailbox in the drop-down on the “From” line of the email.
