If I open nautilus from other applications(f.e. Show in File Browser in Clementine or open a folder in Deluge) it starts as you would expect. The icon in the launcher shows that nautilus is already open however when I click on it, it launches another instance of nautilus instead of focusing on the already open one. What could be the problem here? I'm using Ubuntu 13.04, Nautilus version 3.6.3.