I run a Windows Server 2008 server which is hosting email using hMailServer. SMTP ports are open (verified using portscan). When I try to send an email to juliemullins@***.com (in screenshot attached) I get the following bounceback -
mail.***.co.uk gave this error:
SMTP authentication is required.
where mail.***.co.uk is my mail server.
Log file from hMailServer -
This was working last time I checked a few days ago and can't seem to work out what's going wrong.