So, you sent an email and it was returned or bounced back to you with a message like: Mail delivery failed: returning message to sender
Errors like this are generally encountered when there is an issue on the recipient server, or the intended recipient does not exist on the remote server. It could also be caused by a blacklisted server.
The bounceback message will have this error in the subject, and the body of the message should contain the original message that was attempting to be sent. If you know how to review these emails, they will typically tell you what the issue was. For example, the below bounce specifies:
The following address(es) failed: recipient@RemoteDomain.com
We understand it can be difficult at time to review the full contents of a returned email message, so we created the following tool to help pull the important information for you.
As an example, here is an email that was returned to the sender with the headers included.
Example bounce-back message
Delivery-date: Thu, 25 Oct 2012 16:42:54 -0400
Received: from mailnull by ecbiz103.inmotionhosting.com with local (Exim 4.77)
for firstname.lastname@example.org; Thu, 25 Oct 2012 16:42:54 -0400
From: Mail Delivery System <email@example.com>
Subject: Mail delivery failed: returning message to sender
Date: Thu, 25 Oct 2012 16:42:53 -0400</firstname.lastname@example.org></email@example.com> This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed: recipient@RemoteDomain.com
No Such User Here —— This is a copy of the message, including all the headers. —— Return-path: <firstname.lastname@example.org>
Received: from email@example.com by ecbiz103.inmotionhosting.com with local (Exim 4.77)
for recipient@RemoteDomain.com; Thu, 25 Oct 2012 16:42:53 -0400
Subject: [example.com] Please moderate: “About us”
X-PHP-Script: example.com/wp-comments-post.php for 184.108.40.206
Date: Thu, 25 Oct 2012 20:42:53 +0000
From: WordPress <firstname.lastname@example.org>
X-Mailer: PHPMailer 5.1 (phpmailer.sourceforge.net)
Content-Type: text/plain; charset=”UTF-8″ A new comment on the post “About us” is waiting for your approval
http://example.com/ Author : Payday loans (IP: 220.127.116.11)
E-mail : email@example.com
URL : http://www.paydayspam.com
Comment: Payday loans are available for any occasion!
What Caused this Returned Message?
In the bounceback example above, the cause of the issue is that this user has WordPress setup to allow comments on posts. A spammer attempted to leave a comment on one of their posts and the WordPress administrator of this site has set up their e-mail account as recipient@RemoteDomain.com. So that is theaddress used to send comment moderation requests to. However that e-mail address doesn’t exist on the RemoteDomain.com mail server, so it’s always going to fail and cause a bounce-back error.
Typically these types of bounceback errors are hard bounces, meaning that trying to send the message again won’t be successful. You can read our previous article on why does email bounce, bounceback, or error? for a more in-depth explanation of a hard bounce.
Resolving Mail delivery failed: returning message to sender bounce-backs
Since these are due to multiple reasons, the solutions can vary. Below are the most common solutions to getting your email delivered successfully:
- Check the spelling of the email address for typos
- Check that the person gave you the correct email address
- Remove special characters from To or Subject field
- Create the email account that is receiving/sending mail (if you host it)
- Make sure your domain did not expire (you can see the expiration in the WHOIS record)
- Ensure your MX records are pointing to the correct mail server
- If you suspect a blacklisting contact Live Support
Since this error can be caused by server issues it can be helpful to ask the person you are sending to if they are having any other related problems.
If you happen to also be having issues with WordPress comment spam causing bounce-back errors for your account, we have an advanced article on WordPress comment spam clean up that could help you clear this issue up.