> > > On Mar 26, 2018, at 1:07 AM, Michael Fox <n...@mefox.org> wrote: > > > > Any idea of what's wrong? Or how to find out what's wrong? > > Most likely a firewall is (mis)configured to block STARTTLS. > > -- > Viktor.
You were correct! The IT guys started filtering by domain name in their firewall, which interrupted STARTTLS negotiation. Thanks, Michael
