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Article Selected >> Techniques for minimizing bounced emails

We've increased our mass mailings (transactional and marketing) and an increasing number of emails are being bounced back. Are there ways to minimize the number of undeliverable messages?


Yes, there are proven ways to better assure your emails get through to legitimate email addresses. We will list these in order of priority below, with expected initial efforts first.


1 - Do not allow an email to be sent to an address that has been bounced without first implementing changes to your email server configuration and policies.

The Email Service Provider (ESP) that bounces your message will usually provide a bounce reason. If you ignore this and send another email to the same address without addressing the reasons it was bounced, a complete block of your emails to all recipients in their domain is likely to follow because they know you do not practice proper emailing techniques.

2 - Have SPF and DKIM functioning for your domain

Make sure all of your email server IP addresses are listed in your domain records.  If you have an external vendor using your domain name, make sure all of the IP addresses they might use with your domain are included.  These lists provide the Internet with the authorized IP addresses from which to expect any of your email.

3 - Have Reverse DNS enabled for all email server-related IP addresses

Many receiving email systems now check to see if the domain name resolves back to the IP addresses using this method.

4 - Use separate IP addresses for mass mailing marketing messages and transactional emails

This helps assure that if your mass mailing IP addresses are temporarily blocked, your transactional correspondence still gets through.

5 - Use legitimate UNSUBSCRIBE links in every mass mailing email

Make sure a working UNSUBSCRIBE link appears that assures the email address will be removed in a timely manner from your list.

6 - Put an email policy on your main website, and if you have customers with other domain names which you host, make sure they have a policy listed as well

Email Service Providers can check domains for this policy to determine if you are a legitimate email source. The policy should be clear about the types of communication you allow, the controls you have in place to ensure compliance, and your unsubscribe and abuse reporting policy. For an example, check out the One-to-One policy at

7 - For problem email delivery to certain domains or groups of domains, check their email acceptance policy and follow through with their suggestions

Most ESPs describe how they handle email and suggest ways to get your email through to them.  For instance, if the provider uses Return Path for email authentication, they will have a web page for you to enter all of your contact and technical information.  They will use this information, along with an email loop test (a test that determines if you properly handle unsubscribes), to authorize your emails to their environment.  A great number of larger Email Service Providers use Return Path.  Please see the documents attached to this article for more information on this.  To get your emails delivered, it is NOT required to pay Return Path anything, but that can be helpful, as they will walk you through the process of helping your emails get properly delivered for all of their clients, which subsequently also helps your emails get delivered to other places.

Things to do:

Do NOT ask to be put on a "whitelist" or to have the email loop test done to allow your emails through without first following the suggestions of that domain's email policy page.  You risk being banned for a much longer time.

Do not allow email from any source within your domain to email a bounced address within the expected time-frame for that bounce reason. In other words, if a temporary bounce said a mailbox was full, give that a day or two before re-mailing (it is possible the recipient is on vacation). If a reason is permanent, never send any email to that again.

Double-check all of the IP addresses that can appear in an email header from your domain name and assure those are on your SPF and DKIM records.

Switch to a registrar that can fully support these needs.  One that doesn't is, a widely-used domain provider which has no option for SPF or DKIM records in your domain information.  One that does is

We hope this helps.  Additional information is available in the attached documentation.

Article DetailsSubscribe and Rate this article
Article ID:51097
Date Updated:7/1/2010 9:55:45 PM
# Views:2522
Article Creator:Aaron Malcom
Article Topic:Email Processing
Return Path options.pdf
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