I keep having trouble sending emails to our biggest client. At least a few times a month my IP is listed on spamcop and I get mailer daemons only from their domain (about a dozen email addresses that I deal with there), I don't have trouble sending emails anywhere else. It's been happening for months. I am not an expert with IT, I did a little research and tried a few things but no luck.
I have run virus scans and changed a few settings that my host suggested, but continue to have the problem.
Our host tried to say it was the recipient, our recipient's IT tech said it's our host, then our host said it's our ISP and our ISP said the IP listed isn't theirs so they don't know what to do. I am at a loss and ready to change hosts & ISP's just to try to resolve the problem. Any help would be greatly appreciated!
Host: Godaddy ISP: TPG
Recipient domain: inten com au
Sender domain: a1auscrete com au
Here is an example of a message:
Reason: There was an error while attempting to deliver your message with [Subject: "FW: Young quote"] to (recipient). MTA p3plsmtpa09-08.prod.phx3.secureserver.net received this response from the destination host IP - 216.17.3.48 - 550 , 550 Unable to add (recipient) because host 173.201.193.237 is listed on bl.spamcop.net .
