Are you connected via USB? See if you can log into the web page for the modem -> use either 192.168.1.1 or http://192.168.1.1 & see what options there are. Look for UPnP (Universal Plug & Play.) If you find it, enable it.

Also, did you configure your firewall so it allows LW full access (advisable not to have 2 active firewalls b/c they can interfere with each other); Firewall configuration instructions (click on link)