IMAP - Troubleshooting SSL/TLS Errors

If your mail server work on old outdated TLS V1 you can allow the Splynx server to work with this server by the following config:

For Ubuntu 20.04 (from Splynx 3.1) you should add to file /etc/ssl/openssl.cnf: after line: oid_section = new_oids

openssl_conf = default_conf

[ default_conf ]
ssl_conf = ssl_sect

[ ssl_sect ]
system_default = system_default_sect

[ system_default_sect ]
MinProtocol = TLSv1
CipherString=DEFAULT:@SECLEVEL=1

After that, php7.4-fpm should be restarted by:

service php7.4-fpm restart

Also you can try different IMAP ports: 143, 993