Microsoft Exchange Implementation Note

You must configure your site's name server so Internet-based requests for the Exchange servers you make available to the Internet users resolve to 127.0.0.1. For example, suppose that cluster.mycompany.com is an Exchange server behind your firewall with the IP address 154.23.45.1. You would create a name server record for your ISP (not for internal users) that maps cluster.mycompany.com to 127.0.0.1.

If you cannot do this, users must add an entry to the hosts file for the Exchange server pointing to 127.0.0.1. In Window 95, this file is c:\windows\hosts.