Ports (Security group configuration) in amazon for our email server. Port number 22 80 443 53 25 587 993 995 4190 description SSH : Secure connection to control your machine from SSH client (putty) HTTP (Web interface protocol) HTTPS Secure web protocol ,used to encrypt connection between client and server using SSL/TLS certificates DNS (domain name system):used to resolve IP to names SMTP , protocol used to send emails SMTP submission MSA (message submission agent) port. IMAPS POP3S Sieve Need Required Required Optional (Required if you want to enable SSL/TLS Security) Required Required Optional, required if you want 25 is blocked. Choose between 25 and 587 Required for secure clients Required for secure clients Required
