XFOR: Notes R5 Recipient Cannot Reply to SMTP Message Sent Through Internet Mail Service or SMTP Connector

When you send a Simple Mail Transfer Protocol (SMTP) message to a Lotus Notes recipient, and then the Notes recipient attempts to reply to the message, they may receive a non-delivery report (NDR), and the following event may appear in the event log: In addition, the Exchange Server connectivity administrator log may contain an entry similar to the following: This issue is known to occur when the message is sent to an Exchange Server computer through the Internet Mail Service or to an Exchange 2000 Server computer through an SMTP connector, and then routed to a Notes Release 5 (R5) server through the Exchange Notes Connector. The issue only occurs if the recipient uses a Notes R5 client to reply to the message.

This issue may also occur when you attempt to send a new message from a Notes R5 client to an Exchange Server or Exchange 2000 recipient. In this case, the issue is known to occur when you type the recipient's address in one of the following formats, and then send the message to a Notes R5 server through the Exchange Notes Connector:

• User1@Host1@Domain1
• User1@Host1@SMTP@Domain1
• <User1@Host1>@Domain1

When the Notes recipient replies to the message using a Notes R5 client, Notes removes the display name from the transport Internet address encapsulated by Exchange Server or Exchange 2000 and encloses the Internet address portion in angle brackets. The resulting address appears in a format similar to one of the following:

• <User1@Host1>@SMTP@Domain1
• <User1@Host1>@Domain1

The Exchange Notes Connector does not recognize explicitly encapsulated Internet addresses that contain angle brackets, but no display name, as in the first example above. In addition, the Exchange Notes Connector does not recognize implicitly encapsulated SMTP addresses that contain angle brackets, as in the second example above.

Note that the Notes R5 client only performs this conversion for transport addresses located in the Recipients property.

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 and Microsoft Exchange 2000 Server. This problem was first corrected in Exchange Server 5.5 Service Pack 4.

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