This guide [1] is designed to provide you with essential information about how to harden your Exchange Server 2003 environment. In addition to practical, hands-on configuration recommendations, this guide includes strategies for combating spam, viruses, and other external threats to your Exchange 2003 messaging system.
This is a companion guide to the Windows Server 2003 Security Guide and many of the procedures are related directly to security recommendations it introduced. Therefore, it is recommended that you read the Windows Server 2003 Security Guide before you perform the procedures presented in the Exchange 2003 Security guide.
[Slipstick - Outlook and Exchange News]
[1] http://www.microsoft.com/downloads/details.aspx?familyid=6a80711f-e5c9-4aef-9a44-504db09b9065&displaylang=en
[2] http://www.microsoft.com/technet/security/prodtech/win2003/w2003hg/sgch01.asp