You can use several MS Mail (PC) gateways to provide service between Microsoft Exchange Server and other messaging systems. Within a mixed messaging environment, the Microsoft Mail Connector can act as a gateway postoffice to most MS Mail (PC) gateways and third party gateways.
You can also install an MS Mail Gateway access component on a Connector postoffice. This allows Microsoft Exchange clients access to a foreign system using an existing MS Mail Gateway postoffice. For many mail systems, this is an alternative to installing a gateway postoffice on the Connector postoffice.
The following gateways can be used with Microsoft Exchange Server:
The Microsoft Exchange Server X.400 Connector and Internet Mail Service provide functions that go beyond those of the MS Mail X.400 and SMTP gateways. Thus, the MS Mail X.400 and SMTP gateways cannot be installed on the Connector postoffice. Instead, both the Internet Mail Service or X.400 Connector are used to access either foreign system.