posted this on July 19, 2012 12:31 am
You can use port 25, 587, or 2525 if you're not encrypting the communication between your system and Mandrill or if you want to use the STARTTLS extension (also known as TLS encryption).
SSL is supported on port 465.
ISPs may redirect traffic on certain ports, so it's up to you which port you use. It's just a matter of what you prefer and what works for you.
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