(3rd November 2015).
I have received messages from two clients over the past two days relating to “bounce back” messages being returned from the TalkTalk network.
The messages will carry this text:
Subject: Mail delivery failed: returning message to sender
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:
someone@talktalk.net
host mx-c1.talktalk.net [62.24.202.3]
SMTP error from remote mail server after initial connection:
554-in.ip04nec.int.opaltelecom.net
554 Your access to this mail system has been rejected due to the sending MTA’s poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means.
The message at the bottom in red; “has been rejected due to the sending MTA’s poor reputation.” is one that is being generated by Opal Telecom mail servers.
If you have clients at talktalk.net, tiscali.co.uk, opaltelecom (and many other companies acquired by TalkTalk), then you may see these messages.
What does it mean?
I have checked the mail settings for your accounts and have raised a couple of support tickets and checked with the hosting company. It appears that TalkTalk have made some changes to their mail systems and have possibly been overzealous with the security settings. According to the TalkTalk customer comments site, people are having problems sending mail out as well. I am guessing that these actions are because of the recent security breach at TalkTalk that has been in the press (22/10/2015). You can see details of it here: https://help2.talktalk.co.uk/oct22incident
How do I communicate with Talk Talk customers?
Until either I receive confirmation that there is something wrong at our hosting end, the best advice I can offer right now is use an “out of band” email address. That means use an email address that does not originate from your domain name. Examples would be try sending messages from hotmail.co.uk, gmail.com, yahoo.co.uk mail accounts. It is a short term solution only. This really should not happen, however if things are a mess at TalkTalk right now in the IT department, I can guess how this could happen. There is of course the possibility that mail from these accounts may also get bounced as well.
What happens next?
I will continue to work with the technical support people where your hosting is located, if I find anything new I will place it at the bottom of this article.
How do you know the problem is at TalkTalk?
I don’t, it is speculation. There are a number of checks that can be performed by a receiving server to establish that the sending server is legitimate. I use those methods for your configuration to prevent this type of thing from happening. I have asked Technical Support to confirm that those settings are correct.
There is a check you can do. You can go to here: http://www.mxtoolbox.com and enter your domain name. When the response comes back from the website look for a link which says Blacklist check. Click on that. You would always expect to see all green ticks. In other words you are not blacklisted on the server. If you are listed, that would be a reason for rejecting mail.