Question

I am sending emails via my C# application the way below

MailMessage mail = new MailMessage();
mail.To.Add(srEmail);
mail.From = new MailAddress("[e-mail]", srSender);
mail.Subject = srEmailTitle;
mail.Body = srEmailBody;
mail.IsBodyHtml = true;
mail.SubjectEncoding = System.Text.Encoding.UTF8;
mail.BodyEncoding = System.Text.Encoding.UTF8;
SmtpClient smtp = new SmtpClient();
smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
smtp.UseDefaultCredentials = true;
smtp.Host = "127.0.0.1";
smtp.Port = 25;
smtp.Send(mail);

I am using windows server 2008 R2 and IIS 7.5 but for mail service using IIS 6.0

Now the IIS config is the way below

I am not sure whether this problem caused by IIS or C# application so best to ask it. Thanks for the replays. The problem can be seen at the below i mean multiple received from headers

x-store-info:sbevkl2QZR7OXo7WID5ZcaZ0jeT0hTF6w5JqyzrMGIIJ4/L/t2gj2cA4gOeWpl7k+VkJUhAu0L19pcdx17/6zH+umIRUQcxNC7a6JMdOu4uk+atrpASsFAd6JPSp2WMA
Authentication-Results: hotmail.com; sender-id=temperror (sender IP is 85.17.154.139) header.from=[e-mail]; dkim=none header.d=monstermmorpg.com; x-hmca=none
X-Message-Status: n:0:n
X-SID-PRA: MonsterMMORPG <[e-mail]>
X-DKIM-Result: None
X-AUTH-Result: NONE
X-Message-Delivery: Vj0xLjE7dXM9MDtsPTA7YT0xO0Q9MTtHRD0xO1NDTD0w
X-Message-Info: NhFq/7gR1vQcnWpWXvTdSPoVLSrfQUf9NNYiD+nue1hb767bbTKXz+tuMD66iU4vKsnCmrISnMcViv7BRc8FinIdJij0qRdzfb9MQFyl8Qnq2jH2yHHz6W3BUjjFUEclGZIdpMuV4EQ=
Received: from noreply.monstermmorpg.com ([85.17.154.139]) by BAY0-MC3-F1.Bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4900);
     Sat, 10 Mar 2012 08:20:03 -0800
Received: from XCPV002 ([127.0.0.1]) by noreply.monstermmorpg.com with Microsoft SMTPSVC(7.5.7601.17514);
     Sat, 10 Mar 2012 16:20:03 +0000
MIME-Version: 1.0
From: "MonsterMMORPG"
 <[e-mail]>
To: [e-mail]
Date: 10 Mar 2012 16:20:03 +0000
Subject: =?utf-8?B?UG9rZW1vbkNyYWZ0IGRhaGEga2FsaXRlbGkgYmlyIG95dW4g?=
 =?utf-8?B?b2xhcmFrIGdlcmkgZMO2bmTDvC4gRXNraSBoZXNhYsSxbsSxeiBkdXJ1?=
 =?utf-8?B?eW9yLg==?=
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: base64
Return-Path: [e-mail]
Message-ID: <[e-mail]>
X-OriginalArrivalTime: 10 Mar 2012 16:20:03.0608 (UTC) FILETIME=[A62AC180:01CCFED9]

If you look carefully you will see there are 2 received from headers. I want to make it only single one. So basically removing the second received from header.

Answer 1

Well, do not use the local SMTP server. Every SMTPP server is supposed to add itself to the list for tracking. I do not really understand at all why the heck you bother – this is standard behavior.