XADM: Messages Generate Immediate NDR When Sent to Certain Sites

• Microsoft Exchange Server, versions 4.0, 5.0, 5.5

SYMPTOMS

Any message sent from the local Exchange Server site to another specific site is immediately rejected with a non-delivery report (NDR). The Event Log typically contains 254, 142, and 290 information and warning events similar to the following:

   254 - MSExchangeMTA - X.400 Service - "Unable to correctly route the DN
         ... address using information in the gateway address routing
         table.
         The O/R address matches the local site address space

   142 - MSExchangeMTA - X.400 Service - "The MTA was unable to route the
         recipient DN ... the X.400 address ... the message MTSID... Check
         the routing table for a possible incorrect routing configuration.

   290 - MSExchangeMTA -  X.400 Service - "An NDR has been generated for
         MESSID, it was originally destined for DN ... and was to be
         redirected to ." 

CAUSE

One or more recipients in the local site have additional X.400 e-mail addresses defined in their properties that duplicate the address space or spaces of the destination site for the message.

RESOLUTION

There are two ways to resolve this problem, depending on your configuration:

• If the additional e-mail addresses causing the problem were added in error, you can remove them from whatever recipients have such addresses specified. If the problem occurs suddenly, it is likely that someone has recently created or modified a recipient in the site with an additional e-mail address that duplicates the address space of the other site to which you can no longer send messages. In this case, you can try listing the mailboxes in order of date modified to try to isolate the mailboxes that were changed.



• If the addresses are X.400 addresses and the address space of the other site is truly shared with the local site (up to OU4), you can enable sharing of X.400 address spaces in the Exchange Administrator program (select the "Share address space with other X.400 systems" check box in the Site Addressing object). This option should be used with care, as it disables the sanity checks and makes it possible to create undetected loops if the organization routing is not configured correctly.

MORE INFORMATION

X.400 e-mail addresses for all recipients in a site are scanned each time routing is recalculated, and a compilation of these is stored in a property of the Site Addressing object. This property is consulted when the MTA routes messages; if the destination address space of a message matches an address space in this property, the MTA sends an NDR on the message because routing for the message is ambiguous, unless the sharing of X.400 addresses spaces has been enabled (it is not enabled by default).

This behavior is by design and represents normal sanity checking performed by the MTA.

Additional query words: X400 address share routing calculation

Keywords : kbusage XADM exc4 exc5 exc55
Version : winnt:4.0,5.0,5.5
Platform : winnt
Issue type : kbprb