Try changing ports. In LW tools > options > advanced > firewall. Change LW's listening port to 65000 (or something in the range of 49152 - 65535) > apply > ok.

Keep the Windows firewall off (don't run two firewalls together or they'll conflict) & configure the McAfee firewall to allow LW's new port number: Port Forwarding for the McAfee Security Center

When you set up port forwarding, did you use these instructions? Go through the steps again for LW's new listening port: Port Forwarding for the 2 Wire 2701HG-B
LW's listening port, port in the 'manual port forward' box & port forwarded within router setup must all be the same number.

If none of that helps & you're sure that you've done everything properly, there are more connection fixes to try here: If LW Will Not Connect