Make sure you kill any firefox process that is still running. You probably have an error in the path location that the sartup link is pointing to. If you are trying to open two instances at once (I often do that) then you need to use the switch ''''-no-remote'''' See * http://kb.mozillazine.org/index.php?title=Opening_a_new_instance_of_your_Mozilla_application_with_another_profile * [[firefox is already running but is not responding]]