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port 456

Email Glossary

Email Protocols and Ports in 2026: SMTP, IMAP, POP3, OAuth2 Requirements and TLS Configuration

Alaa 28 August 2026

SMTP, IMAP, and POP3 protocols and ports for email: 25/465/587 for SMTP, 993 for IMAP, 995 for POP3. Covers STARTTLS vs implicit TLS, OAuth2 requirements for Gmail Workspace and Microsoft 365, POP3 ...