You're connecting thru a university or school aren't you? If so then that in itself can be an issue. They may have detected your p2p use & slammed some type of a p2p filter or blocked the ports used for p2p.

Do this simple test for us. Using your browser go here: http://www3.limewire.com:6346/ The page should say ‘Test Page was a Success’. What happens when you go there?

Also some more info:
1. What firewalls you have?
2. ram?
3. Hard Disk space available?
4. Connection type? (eg: dialup, broadband, cable, etc.)
5. Modem & router brand name & model numbers?
6. Where are you trying to connect from (home, school, etc.)?
7. What version of Limewire (LW) & Java do you have? (Go to LW's menu Help>About LW...)
8. Who is your ISP provider?