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I am very sad that my legit emails drops to spam box while i receive many spam emails into my inbox. I very rarely send announcement emails to my all registered members (over 400k right now) but most of them dropping the spam box. I am right now comparing one spam email and 1 email sent from my server. It is incredible that spam sender passes everything while i fail.

The below from spam sender

Authentication-Results:; sender-id=pass (sender IP is; dkim=neutral; x-hmca=pass
X-Message-Status: s1:0:n
X-SID-PRA: Kolay Kacamaklar@knknt <>
X-SID-Result: Pass
X-Message-Delivery: Vj0xLjE7dXM9MDtsPTA7YT0wO0Q9MTtHRD0xO1NDTD0x
X-Message-Info: NhFq/7gR1vTmqm72qFhO+pUA1OKFziMdv5bjOox02XYkBtXmlKIMY4JmO5qxJiwlhREOTGOHuM9QG6kRbemms8RStLmbY7U8eh4d25fnpXQ1vXiD8VHGVTpNQGgJsBcE
Received: from ([]) by with Microsoft SMTPSVC(6.0.3790.4900);
     Wed, 29 Feb 2012 14:05:06 -0800
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; s=knet;;
DomainKey-Signature: a=rsa-sha1; c=nofws; q=dns; s=knet;;
Received: by with SMTP id mAgk5xKyY2s4afl86 Mon, 30 Jan 2012 00:04:42 +0200
Received: (qmail 7844 invoked from network); Mon, 30 Jan 2012 00:04:42 +0200
list-unsubscribe: <>,<>
Content-Type: multipart/alternative;
Date: Mon, 30 Jan 2012 00:04:42 +0200
Message-ID: <koyvUx=TUNN8h8$-Fv1YEB0u9v$koyvUx=TUNN8h8$>
thread-topic: LOKN - Msnniz varmi
X-Mailer-SenderId: i3JmPJO2N
X-KonukNet-Contentd-ID: {"id":Kjlvi16Jx7B1G}
From: "Kolay Kacamaklar"  @knknt<> 
importance: normal
Subject: LOKN - Msnniz varmi 
X-OriginalArrivalTime: 29 Feb 2012 22:05:06.0288 (UTC) FILETIME=[31CB8700:01CCF72E]

And now this the email coming from my game ( server

Authentication-Results:; sender-id=temperror (sender IP is; dkim=none; x-hmca=none
X-Message-Status: n:0:n
X-DKIM-Result: None
X-Message-Delivery: Vj0xLjE7dXM9MDtsPTA7YT0xO0Q9MTtHRD0xO1NDTD0w
X-Message-Info: NhFq/7gR1vR2/tk3mTx4qpcYBpD4z9TE0YneWG8TVeLz542JbpQDH0fPkI7chBK4X+cC9sILd0Cv76nvVUP73k9QX3qsgI9HS9rs2TeqE7lEZfvsXhUGXDfgtly1++/OW95jTqDpfU4=
Received: from ([]) by with Microsoft SMTPSVC(6.0.3790.4900);
     Sat, 10 Mar 2012 07:51:48 -0800
Received: from XCPV002 ([]) by with Microsoft SMTPSVC(7.5.7601.17514);
     Sat, 10 Mar 2012 15:51:48 +0000
MIME-Version: 1.0
From: "MonsterMMORPG"
Date: 10 Mar 2012 15:51:48 +0000
Subject: =?utf-8?B?UG9rZW1vbkNyYWZ0IGRhaGEga2FsaXRlbGkgYmlyIG95dW4g?=
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: base64
Message-ID: <>
X-OriginalArrivalTime: 10 Mar 2012 15:51:48.0950 (UTC) FILETIME=[B4127760:01CCFED5]

I am seriously desperate about this. How do i set up ?

I am using C# 4.0 WPF application. Using windows server 2008 R2 and IIS 7.5

thank you

share|improve this question

1 Answer 1

up vote 3 down vote accepted


Configure your server to use a fully qualified DNS name that reserves through a reverse lookup. My own personal mail server would reject your email during the initial exchange, never receiving the content and causing a failed delivery. You server is currently introducing itself to the internet at "XCPV002".

Change your SMTP server's configuration to use its full hostname and make sure that your DNS server has matching A and PTR records.


UTF-8 subject line... probably a bad idea. Looks like gibberish and gibberish looks like spam.

Fix your headers. Both the From: and Sender: headers are showing up on two lines. Figure out why it shows up and remove the IP address in the Sender: field.

All the issues from this category relate to the software which is generating your email before your SMTP server sees it.

Follow up

DNS entry looks good.

$ host domain name pointer
$ host has address

Regarding UTF-8: that may vary. If you need it to represent certain characters, then by all means do make use of it. My instinct is that spam filters often weight gibberish characters or misspellings negatively. If your filtering software isn't UTF-8 aware, it will just see the ASCII line above.

Where you site may have non-English users, UTF-8 is required for representing many languages, and most of the Internet has "gotten there," it may be me that needs to revisit that view. From that perspective, test the other changes out and see if they're enough. It may be that UTF-8 is just fine these days.

share|improve this answer
Thanks but i need more detailed information. If i were experienced like you i would not waste my time to ask here. I also setup reverse lookup but i don't know why that fails with hotmail. –  MonsterMMORPG Mar 10 '12 at 12:44
@MonsterMMORPG I pointed to which parts of the system are responsible for the different issues, but I'm not sure that I can go much further than that without getting my hands dirty. –  Jeff Ferland Mar 10 '12 at 14:26
hello. made some improvements as you said. can you check my a record and ptr record are correct ? also i don't get why utf8 subject is bad ? thank you. –  MonsterMMORPG Mar 10 '12 at 15:53

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