TMG Allow SSL request on an additional port

“12204 The specified Secure Sockets Layer (SSL) port is not allowed. ISA Server is not configured to allow SSL requests from this port. Most Web browsers use port 443 for SSL requests.”

To add non SSL port:

Create vbs scrript

For example 8455 port, change this on your port

Dim root 
Dim tpRanges 
Dim newRange 
Set root = CreateObject("FPC.Root")
Set tpRanges = root.GetContainingArray.ArrayPolicy.WebProxy.TunnelPortRanges
set newRange = tpRanges.AddRange("SSL 8455", 8455, 8455)

tpRanges.Save

run this script from cmd  running as Administrator using cscript command.