You need to make sure that the OneCare firewall's configured to allow LW.
Try port forwarding for your router, the instructions are here.
Port Forwarding for the Westell D90-327W15-06
LW's listening port, port in the 'manual port forward' box & port forwarded within the router all have to be the same number.
Is it just the firewall problem, or is your LW not connected to the network at all?