Topic Last Modified: 2006-06-05

The Microsoft® Exchange Server Analyzer Tool queries the Active Directory® directory service for X.400 connectors. If the Exchange Server Analyzer finds X.400 connectors present in the Microsoft Exchange organization, the Exchange Server Analyzer displays a warning. The warning indicates that the X.400 connector, a protocol that is used to transport messages between previous messaging systems, is not supported in Microsoft Exchange Server 2007.

In Microsoft Exchange 2000 Server and Microsoft Exchange Server 2003, Simple Mail Transfer Protocol (SMTP) was made the default transport protocol. Although X.400 connectors are supported in Exchange 2000 and Exchange 2003, they are not supported in Exchange 2007 because the use of X.400 connectors has declined over the years. If X.400 support is still required, it is recommended that you keep an Exchange 2000 or Exchange 2003 server. Otherwise X.400 connector can be replaced with SMTP.

For more information about X.400 transport architecture in Exchange 2003, see "Exchange Server 2003 Message Routing" (

For more information about how to implement the X.400 connector in Exchange 2003, see "Implementing the X.400 Connector - Is It Worth Using with Exchange Server 2003?" (

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