ActiveSync does not work with Port Forwarding

Hi,

I configured Exchange 2013 behind TMG and the following works fine

• OWA
• ActiveSync
• Exchange Anywhere

I'm trying to migrate TMG to alternative firewall but when configured with port forwarding only OWA works. ActiveSync and Exchange Anywhere don't.

I then try to configure TMG to use port forwarding instead of Web Listener and the same occurs, ActiveSync and Exchange Anywhere do not work. Looking at the log, I found that every time I tried logging in using ActiveSync, a NON-SYNC packet occurs. Any idea what I should do to make ActiveSync and Exchange Anywhere work with port forwarding?

Thanks.