Protocols
Note that all these protocols can be layered atop TLS
POP3 - port 110 ; STARTTLS can be on this port, or on 995 (POP3S)
IMAP - port 143
IMAPS (IMAP over SSL) - port 993
SMTP - port 25; client SW typically use 587 (plaintext) or 465 (TLS)
ESMTP servers can use TLS; avoid MITM attacks by DANE (part of DNSSEC)
SMTP-Strict Transport Security (relies on CAs).
OS X 10.4/5 Email Clients
OS X Mail.app - TLS 1.0/1.1
TenFourBird (Thunderbird 38) - email & USENET newsgroups; about:config is in General
section of Advanced tab ("Config Editor")
Mailsmith - POP3 only
Seamonkey - email & USENET newsgroups
Provider Settings
Gmail : imap.gmail.com, port 993, TLS/SSL
SMTP: smtp.gmail.com, port 465 or 587, TLS/SSL
Yahoo: imap.mail.yahoo.com, port 993, TLS
SMTP: smtp.mail.yahoo.com, port 465 or 587, TLS/SSL yes
envKan...
CenturyLink/Embarq: username is full email address
IMAP: mail.centurylink.net, port 993, TLS/SSL
POP: pop.centurylink.net, port 995, SSL/TLS
SMTP: smtp.centurylink.net, port 587, STARTTLS
Crim...: envGash2
Mailfence: imap.mailfence.com, port 993, TLS/SSL
smtp.mailfence.com, port 465, TLS/SSL
Newton.org: normal IMAP & SMTP ports
crim...VGX, varFal...
Outlook.com/Office 365 mail: IMAP server = outlook.office365.com, port 993, TLS
POP3S: outlook.office365.com, port 995, encryption TLS
SMTP: smtp.office365.com, port 587, STARTTLS, can req. TLS 1.2
Lumos: mail.lumos.net - incoming (110, STARTTLS) & outgoing