My Server has 2 IP addresses. (IPs are for example only) 1.2.3.4 1.2.3.5 Under IIS, I have a Virtual SMTP Server on 1.2.3.4 and also 1.2.3.5 on port 25. 1.2.3.4 is mapped to my hostname, first.mydomain.com 1.2.3.5 is mapped to my hostname, second.mydomain.com When I send an Email using second.mydomain.com - it works, but it shows up in headers that the email is coming from 1.2.3.5 and then is send from 1.2.3.4. It needs to be send directly from 1.2.3.5 example: Received: from mydomain.com (first.mydomain.com [1.2.3.4]) by net3-nl-mx-19.vevida.net (Postfix) with ESMTP id C4BAE16D0076 for <myemail@email.com>; Thu, 21 Apr 2011 16:47:57 +0200 (CEST) Received: from VPS-T7GLFD2MRH2 ([1.2.3.5]) by mydomain.com with Microsoft SMTPSVC(7.5.7601.17514); Thu, 21 Apr 2011 16:47:54 +0200 Any ideas? Cheers

For IIS questions, please post in http://forums.iis.net/ forums. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration

My Server has 2 IP addresses. (IPs are for example only) 1.2.3.4 1.2.3.5 Under IIS, I have a Virtual SMTP Server on 1.2.3.4 and also 1.2.3.5 on port 25. 1.2.3.4 is mapped to my hostname, first.mydomain.com 1.2.3.5 is mapped to my hostname, second.mydomain.com When I send an Email using second.mydomain.com - it works, but it shows up in headers that the email is coming from 1.2.3.5 and then is send from 1.2.3.4. It needs to be send directly from 1.2.3.5 example: Received: from mydomain.com (first.mydomain.com [1.2.3.4]) by net3-nl-mx-19.vevida.net (Postfix) with ESMTP id C4BAE16D0076 for <myemail@email.com>; Thu, 21 Apr 2011 16:47:57 +0200 (CEST) Received: from VPS-T7GLFD2MRH2 ([1.2.3.5]) by mydomain.com with Microsoft SMTPSVC(7.5.7601.17514); Thu, 21 Apr 2011 16:47:54 +0200 Any ideas? Cheers Sanderb, Because it's sent from that system, the system will send the headers but the IP address will still remain the primary address. I'm not sure why everyone is under this unimagineable impression that multiple IPs is required. The only thing you require multiple IP's for is routing. You don't even require the second IP address. Web address naming is all DNS play... has nothing to do with Routing. The only time you would need multiple IPs is if you are routing to multiple servers by the external route they come in on. That's even for sloppy IIS or Apache management that only use Wildcard Headers... or load balancing which is understandable for multiple IPs with DIFFERENT servers. Example: Web Server setup as a Sharepoint server hosting 40 internal/external sharepoint sites can use the same IP and the same Port for that matter. Just using Cnames internally to redirect the headers. Those 40 names are all Cnames pointing to the host record(external DNS) that points to the public IP. Then there are internal CNAMES that are pointing to server##.mydoamin.com(internally) FQDN. Using Cnames in DNS you can effectively forward hostname traffic to the single IP. Even with an Exchange server, you can route multiple domain names through a single exchange server if the internal domain is the same. CNAME: first > Server.mydomain.com CNAME: second > Server.mydomain.com http://www.ietf.org/rfc/rfc1035.txt - DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION CNAMEs are only an Alias to a host record. Essentially, your 1.2.3.5 is only an Alias to your 1.2.3.4 IP... your 1.2.3.4 IP is the host IP for networking. Mr. X, this isn't an IIS thing buddy.. it's DNS tricks and IP connectivity :) Hope your day is well. Take care! Best Regards Both! Steve Kline Microsoft Certified IT Professional: Server Administrator Microsoft Certified Technology Specialist: Active Directory, Network Infrastructure, Application Platform, Windows 7 Microsoft Certified Product Specialist & Network Product Specialist Red Hat Certified System Administrator This posting is "as is" without warranties and confers no rights.

Hello Steve, I suggested posting in IIS forums because I have not understood well what the user said (I am not used to work on IIS) :) Have a good day and take care also