cPanel Server Email to Gmail marked as Spam, SPF, DKIM, and rDNS pass

Question

Having this issue on a cPanel server 11.34.1 that hosts multiple domains. Email originating from this box on the sendingdomain.com address is flagged as Spam by Gmail. I've implemented SPF and DKIM, both of which pass in the email header below. The sending IP is not on and blacklists & rDNS is setup and resolving properly. I'm at a loss at what else to try and get this issue resolved.

Delivered-To: [email protected]
Received: by 10.182.141.9 with SMTP id rk9csp207963obb;
    Wed, 20 Feb 2013 03:41:05 -0800 (PST)
X-Received: by 10.66.251.129 with SMTP id zk1mr53632663pac.9.1361360464859;
    Wed, 20 Feb 2013 03:41:04 -0800 (PST)
Return-Path: <[email protected]>
Received: from newredwood.sendingdomain.com (newredwood.sendingdomain.com.     [xxx.xxx.xxx.xxx])
    by mx.google.com with ESMTPS id zt7si19804948pbc.152.2013.02.20.03.41.04
    (version=TLSv1 cipher=RC4-SHA bits=128/128);
    Wed, 20 Feb 2013 03:41:04 -0800 (PST)
Received-SPF: pass (google.com: domain of [email protected] designates xxx.xxx.xxx.xxx as permitted sender) client-ip=xxx.xxx.xxx.xxx;
Authentication-Results: mx.google.com;
   spf=pass (google.com: domain of [email protected] designates xxx.xxx.xxx.xxx as     permitted sender) [email protected];
   dkim=pass [email protected]
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sendingdomain.com;     s=default;
h=Message-ID:Subject:To:From:Date:Content-Transfer-Encoding:Content-Type:MIME-    Version; bh=kpYel1IlDvqXEUc0SyIpXbMte3XpQOCXHl+zTyHQvGc=;
b=sGVY6xFKxNKQdpKAtpNaarqLtBD1fgnYUpL+53Hq9GExMz9u2MscfuKMv35y+Gct2uCSIu8FOyAuKeFCUHfIqwc6W4PM+cWNxiSir1CdJmU6UzYIagu1ttD7/AsCEv1dWU9l9rfE5KXAl44kNoaNGt2Z8vxlOCLYiirsqG4hpSE=;
Received: from localhost ([127.0.0.1]:36570 helo=sendingdomain.com)
by newredwood.sendingdomain.com with esmtpa (Exim 4.80)
(envelope-from <[email protected]>)
id 1U882o-00059a-Ro
for [email protected]; Wed, 20 Feb 2013 03:41:02 -0800
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8;
 format=flowed
Content-Transfer-Encoding: 7bit
Date: Wed, 20 Feb 2013 03:41:02 -0800
From: [email protected]
To: <[email protected]>
Subject: 6
Message-ID: <[email protected]>
X-Sender: [email protected]
User-Agent: Roundcube Webmail/0.8.4
X-Media-MailScanner-Information: Please contact the ISP for more information
X-Media-MailScanner-ID: 1U882o-00059a-Ro
X-Media-MailScanner: Not scanned: please contact your Internet E-Mail Service Provider for details
X-Media-MailScanner-SpamCheck: 
X-Media-MailScanner-From: [email protected]
X-Spam-Status: No
X-AntiAbuse: This header was added to track abuse, please include it with any abuse report
X-AntiAbuse: Primary Hostname - newredwood.sendingdomain.com
X-AntiAbuse: Original Domain - gmail.com
X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12]
X-AntiAbuse: Sender Address Domain - sendingdomain.com
X-Get-Message-Sender-Via: newredwood.sendingdomain.com: authenticated_id:     [email protected]

6

Solution 1

A large part of Google's (or any other ISPs) spam detection system is based on the IP reputation of your server. If your IP has a low reputation, then it will be flagged as spam regardless of DKIM/SPF passing.

You will want to check your reputation at http://www.senderscore.org/

Also for WHM, you may want to have Email be routed according to the site's IP. This can reduce cross-site impact if you have multiple IPs or allow you to get around an inherited bad IP.

http://docs.cpanel.net/twiki/bin/view/AllDocumentation/WHMDocs/EximDifferentIps

Solution 2

Follow the Google bulk sender guidelines here, and if you are, but still getting your emails marked as spam, there's a quick "further troubleshooting" page here, culminating in a contact link for their bulk email support team.

They should be able to provide much better assistance than anyone here would.

Comments

[emtunc]

Is all e-mail rejected as spam by sendingdomain when sent to gmail? Have you tried sending an e-mail manually from sendingdomain to a gmail address with just plain text - it could be the contents of the e-mail which is being marked as spam?

[ceejayoz]

Try sending an e-mail with contents more normal-looking than "6"...

[bmurtagh]

@ceejayoz, i did use some generic test messages from other email and same result. I get the "Why is this message in Spam? It contains content that's typically used in spam messages." banner in Gmail.

[Philip]

Try sending a message with just the contents "test test test". If it's still "detected" then it's your IP or a configuration error somewhere. Try sending an e-mail to [email protected] to double-check that.

[bmurtagh]

@ChrisS, i sent a blank email with just the content "test test test" and still labeled as spam. Below is the results from the auth test: SPF check: pass DomainKeys check: neutral DKIM check: pass Sender-ID check: pass SpamAssassin check: ham

[Philip]

Google has something against your IP/Server... You'll have to contact their team as mentioned in Hopeless's Answer and pray that they respond.

[bmurtagh]

Senderscore for the IP is 97. I'll look into the possibility of email being routed by site IP, I'll need to see how the vhosts are configured

[karvonen]

I wonder who/where can really make use of Senderscore. I am running a server sending thousands of emails a month. The classification is "insufficient emails seen". On the other hand my very, very low-output server that sends ~200 emails/month from users IS classified.