Choose either using UPNP or port forwarding. If your router supports UPnP, enable it within the router & then choose the UPNP option within LW's tools > options > advanced > firewall config. Just remember that some routers aren't so reliable in UPnP mode (eg some Linksys models) & there was a recent MS update which caused problems with UPnP for some people. Use the forum search if you want more info about this. IMO, port forwarding would be the best thing to try.

If you've set up port forwarding for your router, you should be forwarding the port that LW listens on. Tools > options > advanced > firewall config. There you'll see LW's listening port. You only need to forward one port number...LW's listening port.

Did you follow instructions from this site????
PortForward.com - Free Help Setting up Your Router or Firewall

If you can find your router in the list, then choose LW from the list of programs. Now you'll see detailed instructions for port forwarding. Don't forget the step of setting up a static IP, if it's in the instructions. LW's listening port, port in the 'manual port forward' box & port forwarded within the router all have to be the same number

If you're still stuck then please give us your system details, otherwise we don't have a clue what's going on with your setup.
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