I am pretty sure. Else it may be a certificate problem, which I could exclude in my case. Try openssl s_client -connect imap.domain.net:993 or openssl s_client -connect imap.domain.net:993 -ssl3 (should or better may fail) openssl s_client -connect imap.domain.net:993 -tls1 (should work)
CONNECTED(00000003) 17589:error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure:s3_pkt.c:1099:SSL alert number 40 17589:error:1409E0E5:SSL routines:SSL3_WRITE_BYTES:ssl handshake failure:s3_pkt.c:536:
OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE NAMESPACE AUTH=PLAIN AUTH=LOGIN] Dovecot ready.
SSL / TLS (Recommended) User name : adress@domain.net Password : your password Server in : hosting24.hostway.net IMAP Port: 993 POP3 Port: 995 Server out : hosting24.hostway.net SMTP Port: 465 The authentication is required for IMAP, POP3 and SMTP.
Non-SSL Settings (Not recommended) User name : adress@domain.net Password : your password Server in : mail.domain.net IMAP Port: 143 POP3 Port: 110 Server out : mail.domain.net SMTP Port: 587 The authentication is required for IMAP, POP3 and SMTP.