[ubuntu] launcher disappeared in unity 3D

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http://ubuntuforums.org – I fear this to be an elementary question, but Ill take the hit just to get some help! Short story : using Ubuntu 12.4, launcher, compiz - all good. Control left mouse stopped working, after much research I removed compiz, ran up 2D session, all good. But now logging back on to a Unity 3D session, my launcher bar (on the left) has gone. So has the Unity plugin in Compiz. Im back with the Applications/Places dropdowns on the top bar, and the active windows on the bottom (Windows style). I confess I was in the middle of some code development, and I havent paid too much attention to the desktop (Hardware)