Client automatically changes account setting, creating "SMTP server doesn't support STARTTLS" error message

I have my account setup and working, using IMAP & SMTP.

Everything works fine for some time, then suddenly I get error messages about “SMTP server doesn’t support STARTTLS”.

When I view the Account Settings, I find the Server Security Policy has switched to “Force usage of SSL/TLS”, which is  not  what I set it to…

So I change it to “Use SSL/TLS if available”, then click  OK , and it works again.  For a while.

Then suddenly, back to the “SMTP server doesn’t support STARTTLS” error message.

I open the Account Settings, and the Server Security Policy is switched back to “Force usage of SSL/TLS” again…

This has happened multiple times.

Why does the client keep changing this setting on me?


Change it to port 993 and use SSL/TLS on special port. See if that makes any difference.