Help - UPnP
Windows XP includes a service that enables discovery of UPnP (Universal Plug-n-Play) devices on your home
network. This service is called the "SSDP Discovery Service", and if you have a UPnP-compatible router on
your LAN, this service will detect it and attempt to help with port-routing issues. If such a router
is detected, DirectX will use the UPnP service when creating DirectPlay sessions to facilitate Internet
games thru the router.
However, sometimes when DirectPlay asks the UPNP service to map UDP port 6073 on the router, the mapping somehow fails and prevents DirectPlay from creating the session, and then FS2004 can't find the session in SBRelay.
Some users have reported that disabling UPnP fixes the problem. To do this, go to the configuration settings of your router and look for UPnP or "Universal Plug-n-Play" and turn it off.
If that doesn't help, try this workaround that several users have reported having success with:
Disable the UPnP service in Windows XP. Go to the Windows Start button, and then Control Panel (or Settings / Control Panel). Then double-click "Administrative Tools", and then "Services". From the Services console, double-click the entry called "SSDP Discovery Service", press the Stop button to stop the service, and then set the "Startup type" to "Disabled". Then click OK to close the window. Then reboot your machine. If you have trouble disabling the service (such as if you're running a non-English version of Windows), you can also download this tool from grc.com to do it for you.
Then start SBRelay and FS2004, and see if FS2004 can find the session.