Uninstall Java, then reinstall it using the "Offline" Java installer, ie: downld the installer to your computer, don't install over the net. See this link & follow steps 1-3 Fixes for Limewire

Rather than turn your firewall off, configure it. 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)

If you have a dsl/adsl/cable or satellite modem or router, make sure UPnP (Universal Plug & Play) is enabled.