The default Microsoft Exchange Server Simple Mail Transport Protocol (SMTP) domain name is based on the organization and site name you specified during installation. For example, Ferguson and Bardell's organization name (FAB) and site name (NAmerica-SW) are used to generate the following domain name.

namerica-sw.fab.com

The domain name is appended to the mailbox name to generate an SMTP address for messages sent through the Internet Mail Service. For example, a user named Fran Wilson sending an SMTP message from this site has the following SMTP address:

franwilson@namerica-sw.fab.com

It is important to verify that the SMTP address for the site is the same as the address you specified in DNS or the hosts file.

    To check the SMTP site address

1. In the Administrator window, choose Configuration.
2. Double-click Site Addressing.
3. Select the Site Addressing property page.
4. If the SMTP site address is incorrect, edit it. Make a note of the site address for later use.

For more information about site addresses, see Microsoft Exchange Server Concepts and Planning and Microsoft Exchange Server Operations.