Hello, my name is Chris and I work for 2Dialog. We are an ESP so we send emails for our clients. We do not allow them to send spam, buy lists, share lists, etc. We also press best practices on our clients all the time. Of course, not all clients adhere to our suggestions, but most do. Anyway, one of our top clients (a very well known corporation) has been seeing some bounce messages from shaw.ca email addresses. They contacted us today as a few of their subscribed members have contacted them saying they have not received any emails. They even have two members of staff who are in the same boat. Now you can see, this is causing an issue with our client, and therefore, with us.
Here is the bounce message we are receiving: "smtp;550 #5.1.0 Address rejected."
In the past two months, we have received this bounce message nearly 1,500 times and a lot of them are the same email address so I don't think they are bad-mailbox (not real addresses) bounces since their subscribers and employees are complaining about it.
Is there some way to get on your whitelist or some way to remove our IPs from any sort of blacklist or blocklist that you may have? Perhaps any specfic server settings we can use to throttle our messages to get them to your inboxes. How many per hour, how many max connections, etc. Things of that sort would also be greatly appreciated.
Thanks so much for your time and I look forward to your response!