Security
Email
Intermediate
Email encryption with TLS-secure SMTP, POP3, IMAP
Enable TLS encryption for email servers (SMTP, IMAP, POP3) to protect messages in transit.
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Network Operations
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Email TLS encrypts messages between email clients and servers. Without TLS, email passwords and content transmit in plain text over the internet.
Email TLS ports
| Service | Port | Encryption |
|---|---|---|
| SMTP | 587 (STARTTLS) / 465 (SSL) | TLS |
| IMAP | 143 (STARTTLS) / 993 (SSL) | TLS |
| POP3 | 110 (STARTTLS) / 995 (SSL) | TLS |
Configure TLS on server
# Postfix SMTP TLS
smtpd_use_tls = yes
smtpd_tls_cert_file = /etc/ssl/certs/mail.crt
smtpd_tls_key_file = /etc/ssl/private/mail.keyClient setup (Outlook, Thunderbird)
- SMTP: server.com, port 587, TLS/STARTTLS
- IMAP/POP3: server.com, port 993 (IMAP) or 995 (POP3), SSL/TLS
- Use your email address and password
Always use TLS for email
Unencrypted email (port 25, 110, 143) sends passwords in plain text. Always use TLS.
Related: TLS versions | SSL errors
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