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Since I upgraded to Precise 12.04, I've been having troubles with Unity3d, as my graphics card drivers don't seem to work. I've tried reinstalling them, downgrading them, and reinstalling unity. Whenever I try to do so, it won't let me, saying:
The following packages have unmet dependencies: gnome-tweak-tool : Depends: gnome-shell but it is not going to be installed E: Unable to correct problems, you have held broken packages.
Does anyone know how to solve the broken packages problem? I've looked everywhere and I'm desperate. Thank you for your attention.