Simple Mail Transfer Protocol (SMTP)

What is Simple Mail Transfer Protocol (SMTP)?

SMTP is the most preferred protocol for sending email messages between email servers. The protocol follows the rules on the interaction between a program receiving email and a program sending email, including RFC 5321 and RFC 821.

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• Conversion
• Unique Open Rate
• Cloudmark
• Multipurpose Internet Mail Extension (MIME)
• Bounce Message
• Alias
• DomainKeys Identified Mail (DKIM)
• Inactive Subscriber