Applies to: Exchange Server 2007
Topic Last Modified: 2007-06-15

Use the Error Message dialog box on the Add IP Block List Provider control to determine the response to be delivered in the Simple Mail Transfer Protocol (SMTP) session to senders whose messages are blocked by the Connection Filter agent when an IP Block List provider service matches the sender's IP address.

Default error message

To send a standard SMTP 550 error message to blocked senders, select Default error message.

Custom error message

To compose and send a customized error message, select Custom error message, and then type the message text in the text box.

We recommend that you specify the IP Block List provider service in the response so that legitimate senders can contact the IP Block List provider service, as in the following example: Originating IP addresses matched contoso.com's IP Block List provider service.

For More Information

For information on connection filtering and IP Block list functionality, see the following topics: