Can you give us a total desciption of your set up:
1. Do this simple test for us. Using your browser go here: http://www3.limewire.com:6346/ The page should say 'Your test worked!'. What happens when you go there?
2. What firewalls you have?
3. How much ram?
4. Hard Disk space available?
5. Modem & router brand name & model numbers?
6. Where are you trying to connect from (home, school, work, etc.)?
7. What version of Limewire (LW) & Java do you have? (Go to LW's menu Help>About LW...) Will show both LW & Java version.
8. Who is your isp provider (Internet Service Provider)?
9. Are you sharing the connection with other computers or p2p sharing programs? If yes, please give details of set up.
10. Is this a your 1st try at LW or is this a new problem with an experienced user.

Does avast have a capacity to clear certain programs? Some av & adware/spyware programs do require to give clearance for LW. I'm not sure which ones do this.
BTW not wise to have 2 active firewalls as they can interfere with each other, so if you have 2, disable one & configure the other.

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