XCON: Messages Are Lost When the Domain Controller Is Unavailable

If you attempt to send messages through an Exchange Server 5.5 computer, and the domain controller becomes unavailable in the domain in which the Exchange Server 5.5 computer is a member, some of the messages may be lost. When this problem occurs, you do not receive a non-delivery report (NDR), and the messages are never delivered.

This problem occurs when the message transfer agent (MTA) cannot obtain the information it needs to deliver the messages from the directory service. The domain controller must be available for the MTA to obtain this information.

To resolve this problem, obtain the latest service pack for Exchange Server 5.5. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in Microsoft Exchange Server version 5.5. This problem was first corrected in Exchange Server 5.5 Service Pack 4.