Actually I just had a friend who run into the same problem. The mail settings were configured properly for SSL:
IMAP: imaps.bluewin.ch:993 (SSL)
SMTP: smtpauths.bluewin.ch:465 (SSL)
The server refused connections so no mail send/receive was possible at all.
What worked however was to use imap.bluewin.ch:143 and smtpauth.bluewin.ch:587, those ports should still negotiate TLS if configured properly on server side.
But I would prefer to use dedicated SSL-only connection to port 993 (IMAP) and 465 (SMTP) but somehow the servers seem to be wrongly configured.