No, SMTP client connection from a PHP application
I’m assuming when you say “ses” you are talking KumoMTA, right?
@youthful-zorse That image above was me testing the connection to the pphosted address that was blocking @welcoming-rabbit’s email. Yes I used Telnet, because it is quick and easy and it proves the connection.
An update. A kind person over at Proof Point must have seen my support request, and green-lit our connection. Mail is flowing through now without issue, and I’m not seeing lockups. I think the next stage will be to deal with Gmail, and I’ve already added the necessary “one click unsubscribe” headers into the mail to meet their 5,000+ emails a day rules there. Just not sure how long it takes them to realize it and for the IP/domain to be blessed. We’ll see, I guess.
Great! I highly recommend tuning down your shaping a bit to let the IPs warm slower or you may see more of these. Keep an eye on those tranfails and DO WHAT THEY SAY. The ISP’s job is to protect their user inboxes, not to let your email pass, so they usually give very informative notices in the Transient and permanent failure responses.