DOCUMENT:Q229961 06-AUG-2002 [exchange] TITLE :XFOR:Applying Restrictive Address Space on Internet Mail Service PRODUCT :Microsoft Exchange PROD/VER:winnt:4.0,5.0,5.5 OPER/SYS: KEYWORDS:kbenv ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 ------------------------------------------------------------------------------- SUMMARY ======= Using incorrect address spaces in the Internet Mail Service (Internet Mail Connector in Exchange Server 4.0) other than the default wildcard (*) entry can cause unexpected routing to occur with multiple Internet Mail Services configured. Non-delivery of outbound mail is also possible. This article explains how to configure the Internet Mail Service properly, and why. MORE INFORMATION ================ Message routing is performed by the Message Transfer Agent (MTA). The address space which best matches the recipient address is selected, based on the following preferences: 1. An exact string match: (for example, recipient = "SMTP:userz@microsoft.com" and address space = SMTP:userz@microsoft.com") 2. A wildcard string match: (for example, recipient = "SMTP:userz@microsoft.com" and address space = "SMTP:*@microsoft.com"). The wildcard string that matches more non-wild characters is given preference. 3. A partial string match: (for example, recipient = "SMTP:userz@microsoft.com" and address space = "SMTP:userz@com"). 4. The address type matches and the address string is blank: (for example, recipient = "userz@microsoft.com" and address space = "SMTP:") The MTA will evaluate the address and decide where to route it, and will do this by comparing the entire address of the recipient to the address space entered in the Internet Mail Service. As the MTA does not work like a Domain Name System (DNS) resolver, it does not strip off the local portion of the address before matching it against the address space string. The whole user address is compared against the whole address space string. A routing table entry of "SMTP:.com" or "SMTP:@.com" will not match a user of address "SMTP:@.com," whereas an entry of "SMTP:*@.com" will match. The MTA will then choose a single connector from the set of connectors that support that address space. As long as the Gateway Address Routing Table (GWART) doesn't change, the same address space will always be chosen during rerouting. Rerouting tries different connectors within the set of connectors supporting this address space. Additional query words: ====================================================================== Keywords : kbenv Technology : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2 Version : winnt:4.0,5.0,5.5 Issue type : kbinfo ============================================================================= 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 2002.