The brick wall represents a firewall. This must be due to something. Possibly your isp. Try going to LW's menu bar, Tools>Options>Advanced>Firewalls & changing Listening port to 64049. Apply. Restart LW.

If still no good, then try deleting your LW Preferences folder whilst LW is closed; instructions here: Point #2 & 3 in Fixes for Limewire (sample image included at bottom of page.) But make a note of all important settings such as days to keep incomplete files because when you restart LW, you'll need to reset your options.