stunnel

mail.conf

Yandex

IMAP: mail.lib.mk
      993
      SSL
      
SMTP: mail.lib.mk
      465
      SSL

Gmail

IMAP: mail.lib.mk
      999
      SSL
      
SMTP: mail.lib.mk
      666
      SSL

SMTP: mail.lib.mk
      667
      STARTTLS

Outlook

IMAP: mail.lib.mk
      996
      SSL
      
SMTP: mail.lib.mk
      581
      STARTTLS