59 An unexpected network error occurred

Hi everyone,

This is a strange one.

We are using a TMG for a VPN (amongst other things such as web publishing etc) 

We are using some software called 2X  to connect to something on a part of our network,  internally this works ok, but users on our VPN cant connect to it, but they can connect to everything else.  2X is a program that connects on port 80. From the VPN we can ping the host that the 2x software connects to, we can even RDP to the servers the 2X software is pointing to (once we set up a standard 3389 rule for this) but it wont work as it should via port 80.  Its something to do with this port 80 connection.

In TMG logs we get - 59 An unexpected network error occurred. 

I have tried a block and allow rule, in various orders but cant get it to work.

Any ideas ?

Thanks