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Okay, so I recently installed Ubuntu 12.04LTS, and at first, Unity 3D worked fine. The Launcher was transparent, the bar at the top had the shadow, and everything looked really neat.
I don't remember why, but for some reason, when I logged in, I clicked on the Ubuntu symbol and chose Ubuntu 2D, and it looked horrible. I hated it, compared to Unity 3D. But I can't get back into 3D anymore. No matter what I do, I'm always running Unity 2D, even if I click on the Ubuntu symbol and select "Ubuntu".
Why am I stuck in Unity 2D even though I keep selecting the 3D one, and how do I fix that?
If it's worth anything, I'm using an nVidia GT440, with the proprietary drivers, version 303 or really close to that.