The same thing happened to me & I was freaking out!! >__< ! Well this will help u if u have mods. When you go into the minecraft folder bin there should be a FOLDER instead of a file that says minecraft.jar (its not real its mods) Your going to want to remove that from it and search for a FILE minecraft.jar. Put that in there instead if already not.. Once your done with that update ^__^ and you can put ur mod thingy back if u want to. ENJOYYY ^____^
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