XCON: SMTP Message ID May Be Incorrectly Truncated

When an Exchange Server computer generates a non-delivery report (NDR) for an SMTP message, the message ID may be incorrectly truncated. For example, if an NDR for a message came from the server yourserver.sub1.sub2.com, the message ID should be as follows: However, Exchange Server generates the following malformed message ID:

The structure that contains the message ID has 128 bytes allocated for the message ID. Because the message ID is created as Unicode, only 64 characters are allowed. The unique number portion of the message is 38 characters in length, which leaves room for only 22 additional characters. If the fully qualified domain name exceeds 22 characters in length, it will be truncated.

To resolve this problem, obtain the latest service pack for Exchange Server version 5.5. For more information, please see the following article in the Microsoft Knowledge Base:

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.5.