If you are connected to an Outlook.com account (personal) or an Office 365 account (work/enterprise), you will always be connected to the modern versions of Exchange Server and will almost certainty be able to use the Trustifi Outlook add-in.
If you are connected to an Outlook.com account (personal) or an Office 365 account (work/enterprise), you will always be connected to the modern versions of Exchange Server and will almost certainty be able to use the Trustifi Outlook add-in.