I just wanted to share my experience. Before I realized Limewire wouldn't connect, I also couldn't establish FTP connection to anything from home (Uverse router). From reading posts and faqs, indications were firewall (software or router). Long story short - I had installed a VPN Client software for work a month or two before. I had exited/shutdown this from system tray during troubleshooting, so didn't suspect it further. Turns out, shutting down from system tray wasn't enough - the software had a security policy that apparently was still active. Once I discovered this, I just had to right-click, "disable security policy", and my connections worked.
So lessons learned - 1) you may have a "firewall" coming from somewhere unexpected. And 2) shutting down is not always shutting down.
Very frustrating.