Make sure that LW's being allowed through the Windows firewall.
User Cant Connect - LimeWire

Try the advice here: all of a sudden will not connect (a fix to try)
Start off by deleting LW's preferences folder & changing Java versions.
You'll know if you've deleted the preferences folder properly...when you start LW, you'll go through the setup wizard again & all the settings within LW's options will have changed.
If you get confused with deleting the preferences folder, have a look at this post (Windows XP).
One bar, connection problems

If nothing there helps, please give us your details...you need to answer all of the questions here. The details you've given so far don't tell us enough about your setup. Click on the blue link below.
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