XCON: Erroneous Deletion of SMTP & SNADS Routes During Routing

• Microsoft Exchange Server, versions 4.0, 5.0, 5.5

SYMPTOMS

You may experience some non-delivery reports (NDRs) when you send messages to SNADS or SMTP (Simple Mail Transfer Protocol) addresses.

CAUSE

During recalculation of the local routing table, routes that are imported from other sites may be dropped. This concerns routes of the form "SNADS =" or "SMTP =" where no routing value is configured.

WORKAROUND

You can temporarily create a LOCAL route that will not be replicated in other sites.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server, versions 4.0, 5.0, and 5.5. A supported fix is now available, but has not been fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information.