My client is getting bounceback messages from my email when they try to send me an email.
I am still receiving regular emails from other sources. But for some reason with this particular email or group of emails, they are unable to send to me anymore. I have no idea why. I have attached the message that my client received when they attempted to send.
All Replies (1)
This is not a Thunderbird issue.
You will need to contact your Email Admin and give them these screenshots. Looks like they have recently implemented rDNS checks and the sending side doesn't have a proper rDNS setup for their mail server and hence email to you is bouncing. Your admin can add them to an allow list so that email can once again flow OR (s)he can insist that the other end fixes the missing rDNS - this is the better solution but one that you have no control over.
Most email servers will give a high SPAM score for mail servers that don't have proper rDNS and ultimately lead to bounced emails such as this.