Why are Google and Others Blocking my Emails?

As a business owner you are well aware of the high level of sensitivity email marketing entails. How many times have you sent out legitimate emails to your customers only to have them blocked by Google, AOL or other email providers? It’s frustrating nonetheless when you know it’s not spam – yet it is viewed as such.

It is no wonder that so many new companies are springing up each day touting new email delivery services. Most of these offer their services for a monthly fee based on the number of subscribers. Examples are Constant Contact, iContact, GetResponse, etc.

These companies usually don’t have issues of being blocked because they are properly set up with IPS’s to show that they are legitimate senders of emails.
One of the ways to do this is by use of a Primary Transversal Record or PTR.

The PTR or Host PTR is a commonly confused concept in the realm of DNS and deserves a simple explanation for reference. A common experience related to the lack of proper PTRs is service providers like Google or AOL blocking outbound emails from businesses.

This is primarily a security and anti-spam policy which blocks email from IP addresses without a corresponding fully qualified domain name.

Remember, a true domain name (www.name.net) is always tied to an IP address. If a domain name is not tied to an IP address or vice versa – this is considered a red flag.

In order to avoid these types of issues, a company would be required to have in place a PTR record which allows for a reverse look up of any IP address to provide the fully qualified domain name. Therefore, Google, AOL and others will look to see if you have a PTR record which would give them the information they need to make sure your business is not in the business of spamming.

Unless a business owns their own autonomous system and can be viewed as an internet service provider then they will be required to request a PTR be created by their internet service provider. The information needed by a service provider to establish a PTR is simple:

Pubic IP Address (W.X.Y.Z) maps to http://www.name.net

This would create the following PTR: Z.Y.X.W.in-addr.arpa. IN PTR name.net

Notes of Importance:
1). Forward delegation is provided by your domain registrar (like a Network Solutions) – http://www.name.net points to W.X.Y.Z – anytime you change Internet Service Providers and obtain new public usable IPs this must be updated with your registrar.
2). Reverse delegation is provided by your ISP – W.X.Y.Z points to http://www.name.net – anytime you change Internet Service Providers you will want to request new PTRs with the new ISP.
3). You must have an A record for http://www.name.net in your DNS zone whether your business or your service provider is hosting your DNS.
4). You will need an MX record in your DNS zone such as mail.name.net which points to A.B.C.D

 

Mark Williams
Contributing Engineer
EtherSpeak Communications, Inc.
www.ietherspeak.com