The Specified Secure Sockets Layer (SSL) Port Is Not Allowed – Forefront TMG Posted on by Webmaster IT Support Forum › Forums › Network & Firewall › TMG › Troubleshooting › The Specified Secure Sockets Layer (SSL) Port Is Not Allowed – Forefront TMG Tagged: SSL This topic contains 0 replies, has 1 voice, and was last updated by Webmaster 4 years, 7 months ago. Author Posts November 5, 2014 at 9:02 am #971 WebmasterKeymaster Forefront TMG gives this error: The specified Secure Sockets Layer (SSL) port is not allowed. Forefront TMG is not configured to allow SSL requests from this port. Most Web browsers use port 443 for SSL requests This means that you are trying to connect using a port that is not allowed through TMG. To fix this, edit or create a new firewall rule for the port you are trying to connect through. Author Posts You must be logged in to reply to this topic.