DOCUMENT:Q262116  20-OCT-2000  [exchange]
TITLE   :XCON: How Exchange Server 5.5 Routes Custom Recipient Messages I
PRODUCT :Microsoft Exchange
PROD/VER:winnt:5.5
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, version 5.5 
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SUMMARY
=======

This article describes how Exchange Server 5.5 routes custom recipient messages
internally.

MORE INFORMATION
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When you send an e-mail message to a custom recipient address, the directory
places the default address in the custom recipient address X.400 proxy address
as a domain-defined attribute (DDA).

For example, if a custom recipient that has a default Simple Mail Transfer
Protocol (SMTP) address of "someone@microsoft.com" has the following X.400 proxy
address

   C=us;a= ;p=Org;o=Site;s=Someone;g=MsGuy

when you send an e-mail message to that custom recipient that has a default SMTP
address of someone@microsoft.com, the message is routed as follows, and is
routed by DDA first:

   C=us;a= ;p=Org;o=Site;s=Someone;g=MsGuy;dda=SMTP:someone@microsoft.com

If the message transfer agent (MTA) cannot find a route, the MTA routes on the
X.400 address. In some cases the custom recipient address is routed to an X.400
connector with a "C=*" address space.

Typically, the message loops when the message is rerouted back to the originating
site.

Additional query words:

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Keywords          :  
Technology        : kbExchangeSearch kbExchange550 kbZNotKeyword2
Version           : winnt:5.5
Issue type        : kbinfo

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