DOCUMENT:Q254214 03-MAR-2000 [exchange] TITLE :XFOR: Routing Restrictions Don't Work w Some Antivirus Solutions PRODUCT :Microsoft Exchange PROD/VER:winnt:5.5 OPER/SYS: KEYWORDS:exc55 ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, version 5.5 ------------------------------------------------------------------------------- SYMPTOMS ======== Routing restrictions may not work after you install Simple Mail Transfer Protocol (SMTP) antivirus software. When you install SMTP antivirus software, the installation places the Exchange Server Internet Mail Service behind an antivirus 'firewall,' as illustrated in the following diagram: (Internet) ----> (SMTP Virus Scanner) ----> (Exchange Server Internet Mail Service) In this configuration, the routing restrictions, specifically the options that require a specific IP address or range of IP addresses, may no longer work. NOTE: Routing restrictions are created on the Routing tab of the Internet Mail Service. A routing restriction is a unit of criteria to allow or restrict incoming SMTP mail. CAUSE ===== When an Exchange Server computer running the Internet Mail Service is placed behind an SMTP virus scanner or virus firewall, as illustrated in the diagram in the "Symptoms" section of this article, then the Internet Mail Service actually only accepts connections from the antivirus software. Thus, when the Internet Mail Service processes the message, it records the source computer as 127.0.0.1 (the local host), so the Internet Mail Service never sees all of the other Internet IP addresses. WORKAROUND ========== To work around this problem, make sure that the first SMTP daemon, the antivirus firewall, is capable of advanced restrictions. STATUS ====== This behavior is by design. MORE INFORMATION ================ For additional information, click the article number below to view the article in the Microsoft Knowledge Base: Q173903 XFOR: Changing the TCP Port Used for SMTP Mail This article describes how to configure the Exchange Server Internet Mail Service and an SMTP based virus scanner to work together on the same computer. After you follow the instructions in this article, each product runs on a different port. For antivirus features, please contact your antivirus software vendor. Additional query words: antivirus norton symantec port 25 av ====================================================================== Keywords : exc55 Technology : kbExchangeSearch kbExchange550 kbZNotKeyword2 Version : winnt:5.5 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2000.