Emails going to Junk for Hotmail recipients [duplicate]

We send daily mass emails to our customers (~30,000+ emails per day). We have problems with Hotmail users receiving our emails. Sometimes the email goes to the Junk folder, but often it will got to their inbox, but the content is blocked so the user sees a message saying "This email was blocked and may be dangerous". If an email is sent to GMAIL it is usually not blocked, but it does show up as from "Uknown" instead of the company.

Please be advised I've done the following: 1. No RBLs Checked on -> http://multirbl.valli.org/ 2. We do have SPF records published 3. We do have reverse DNS setup 4. Our company even signed up for the Junk Mail Reports Program at Hotmail

Here is a sample header, I've noticed the X-SID-Result and the X-AUTH-Result both FAIL every time at Hotmail:

X-Message-Delivery: Vj0xLjE7dXM9MDtsPTA7YT0wO0Q9MTtTQ0w9MQ==
X-Message-Status: n:0
X-SID-Result: Fail
X-AUTH-Result: FAIL
X-Message-Info: JGTYoYF78jFqAaC29fBlDlD/ZI36+S6WoFmkQN10UxWFe1xLHhP+rDthGRZM87uHYM926hUBS+s0q46Yx9y6jdurhN6fx0bK
Received: from privatecompany.com ([WanIPAddress]) by col0-mc3-f30.Col0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675);
     Wed, 5 May 2010 08:41:27 -0700
X-AuditID: ac10fe93-000013bc00000534-46-4be191a1618e 
Received: from INTERNAL-Email-SERVER([InternalIPAddress]) by privatecompany.com with Microsoft SMTPSVC(6.0.3790.4675);
     Wed, 5 May 2010 11:41:21 -0400
From: Private Company, Inc.<[email protected]>
To: [email protected]
Message-Id: <[email protected]>
Subject: 
Date: Wed, 5 May 2010 11:42:46 -0400
MIME-Version: 1.0
Reply-To: [email protected]
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
X-Brightmail-Tracker: AAAAAA==
Return-Path: [email protected]
X-OriginalArrivalTime: 05 May 2010 15:41:27.0837 (UTC) FILETIME=[6D06E4D0:01CAEC69]

The solution I found for Hotmail to quit blocking the content of the email was in the configuration of the mass email formats; this also fixed the problem of gmail recipients seeing our emails as "Uknown Sender".

Examples: Our emails were original sent as "Mr. President " and this would cause hotmail to block the content and for gmail to mark us as unknown sender. However if you get the display name to match the email address it is delivered okay.

It has to be EXACT though; here are some examples -

Good: Mr President <[email protected]>
Bad: Mr. President <[email protected]>
Good: Private Company <[email protected]>
Bad: Private Company, Inc. <[email protected]>

This isn't a direct solution, but would it be possible to use a 3rd party email marketing company to send your emails? This way you don't have to worry about a lot of these issues. ConstantContact.com is one. Eloqua seems to be a popular one for large companies.

Sign up for SNDS (https://postmaster.live.com/snds/index.aspx).

You will get better visibility on why Hotmail is blocking you - could be because your level of complaints is too high or you might be hitting spam traps (old expired Hotmail accounts).

You might also consider adding List-Unsubscribe header to your emails, but its usefulness (for Hotmail) is limited.