How to access a "Shared Mailbox"?
1. Via browser: Open your browser and und type the shared mailbox link: https: //xmail.mwn.de/owa/E-mail address of the shared mailbox (e.g. https: //xmail.mwn.de/owa/it-support@tum.de)
2. Via mail client: You can access the shared mailbox via various clients (Outlook, Thunderbird, ...).