japes try this: Try deleting your LW Preferences folder whilst LW is closed; instructions here:
Fixes for Limewire (I know you said "Tried removing the preference settings with the jar file in these forums.")
1. Try a different port setting: Go to LW's Tools>Options>Advanced>Firewalls & change the listening port to 80 & press Apply button. You may need to close & re-open LW for it to take effect.
If it was working a few days ago & suddenly stopped working & deleting the LW preferences folder didn't work then it looks like your ISP Provider has put filters in place to stop you using p2p programs. This is becoming more frequent nowadays as isp's deal with heavy net traffic.
2. Try a proxy:
A Fix for those whose ISP's block Limewire pages 1 & 2 which has a link to alternative instructions.
Another Insight proxy solution http proxies A Successful http Proxy Solution