Weird problem with the Genero Desktop Client

I am experiencing a very weird problem with the Genero Desktop Client and I
was wondering if anyone else has seen or heard of anything like this. or if
anyone may have any suggestions.  The computer I am having this issue on is
able to connect to our system, and start our applications but the user never
sees a GUI window.  The Windows XP firewall has an exception for port 6401
in it.  I can send a "front call" command  (which uses the same port as the
GUI) through a 4gl program to open an application on the user's pc with no
problem, they just can't see our applications.  Normally the fglrun command
on the server will "die" after one minute if it doesn't get a connection
back to the user's pc.  Does anyone have any advice?  Thank you in advance.

Thank you, 
Norman