Is LW connected at all (it's possible to be connected with the firewall icon showing)??
If LW isn't connected: In LW file > disconnect. Wait a few minutes, then file > connect.
Try deleting LW's preferences folder when LW's properly closed. See point 3 here .
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things including listening port number. If you're not sure of your settings, go through LW's tools > options & write them all down, so that you can reset things later.