SMTP Cannot send message using the server xyzzy
Every now and then, I get this, and it goes away after a day or two, sometimes longer. But generally only arrives every 4-9 months, then it's gone again.
DNS resolution is working to smtp.mailbox.org (220.127.116.11) though pings time out.
My gut tells me the mailbox.org smtp server is wonky as everything else works, I even receive email from that mailbox. Client is setup using their Mac profiles so it's not that.
Anyone else get this?