Mail-related agreements port:
IMAP protocol: 143 / TCP
POP3 protocol: 110 / TCP
SMTP protocol: 25 / TCP
IMAP with SSL encryption protocol: 993 / TCP
POP3 protocol with SSL encryption: 995 / TCP
SSL encryption protocol SMTP: 465 / TCP
When using unencrypted e-mail and server communication protocol, data is transmitted in clear text, there are problems account password leak.
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