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SAMSUNG GALAXY NEXUS HARD RESET ANDROID 4.0 ICE CREAM SANDWICH

Turn off your phone. First press POWER, and then press VOLUME DOWN then VOLUME UP. (or power then VOL UP then VOL down)

It will bring up a menu that allows you to use volume up and down to cycle through the menu.
BE sure to press the keys in the right order.

select RECOVERY

Once an android with an exclamation appears, press both VOLUME UP + VOLUME DOWN and POWER until reset menu appears