MailSlurp guide agent setup

Title: What Are SMTP Ports? Practical Setup and Troubleshooting Guide
Description: Learn what SMTP ports are, when to use ports 25, 465, 587, and 2525, and how to validate TLS/auth behavior safely in production workflows.
Canonical URL: https://www.mailslurp.com/guides/what-are-smtp-ports/
Markdown URL: https://www.mailslurp.com/guides/what-are-smtp-ports.md

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