Delivery Temporarily Suspended Unknown Mail Transport Error Postfix: Upd _verified_

Title: Decoding the Dreaded “Delivery Temporarily Suspended – Unknown Mail Transport Error” in Postfix

In other words, the error is not in Postfix. The error is that the other server failed at conversation. And Postfix, like a baffled diplomat, can only report: "They said something, but it was not language." like a baffled diplomat

If the mail goes out, you’re done. If not, proceed. can only report: "They said something

postqueue -f