SMTP with StartTLS doesnt seem to work
We switched from 9.1 to 9.8. In setting everything up we also tried to establish an email connector to our Exchange with StartTLS enabled. However, we only get the message:
Authentication failed: 535 5.7.3 Authentication unsuccessful
With security option "None" and Port 25 a connection is easily possible to our Exchange.
This holds also true, if we tried to connect to the smtp of bigger email hoster (like gmail).
For sure we tried any possible combination of options and user names.
Does somebody have similar xp.?