Check the 1st few posts here ISP's known to BLOCK or Filter p2p or specifically Limewire (re: PLusnet) as you may be able to by-pass the issue by changing the port you connect through. Also take a close look here Connection problems? Check here first! (click on link), & check your software firewall settings & also your UPnP settings (or manual port forwarding "if" necessary!) Oh .. & if you do change your connection port, you may need to also change it for your computer's software firewall.