Amazon Web Services’ EC2 instances are throttled on port 25 by default as a spam prevention measure.

SMTP can operate over ports 25, 587, or 2525 but the default port used in an EC2 instance is port 25. 
Post a Comment

Featured Post

Updated Coupons / promo codes for Google Apps for Work / Business

To redeem: 1. Sign up for Google Apps   2. Go to your billing settings  3. Choose your payment plan  4. Enter your promo code ...