Try this...
Right-click the Limewire icon and go to properties and change compatability setting to Windows 2000. (but only if you're using Windows 2000 or later.) Somebody reported changing to Windows NT compatibility fixed their problem despite not using that operating system version.
Right-click on the Limewire icon on the desktop and click on Run as. Then it should come up showing the current user and then switch it over to Administrator. (but 'only' if you're the admin of your comp.!)
If you still have no luck try the preference folder/s again....
Fixes for Limewire when LW isn't operating as it should LimeWire Pref Folder in Vista