Hi,
After installing Exchange 2013 with SSL certificate with OWA, Active Sync and outlook anywhere. I observed that if someone from external network can telnet to my server is able to connect. I checked it and find that port 25 and 587 is open and bypass my Fortinet firewall.
I would like to know how can I block these ports and don't allow anyone can telnet on my Exchange server from externally. Please assist.