It's great when we don't even know what OS you're using, let alone anything else

For Windows: Reinstall this version of Java, use the JRE offline installer. Remove your current version of Java before installing this one.
Java SE Downloads - Previous Release - JDK 5

Now delete LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used much older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things.

Double check that LW's allowed through whatever software firewall you're using. You say that you've looked at all of your firewalls...don't use more than 1 software firewall. Running more than one will just cause trouble as they'll interfere with each other, rather than making you more secure!

If you're still stuck then please give some details.
System details - help us to help you