Please help, my son has bought and been playing the minecraft game for a while now, just recently his pc had a slight melt down which his dad fixed no problem. But now he cant play minecraft, when he loads it up it starts of ok then shuts down, it doesnt run. we looked on line for help and they all suggest java update, driver update etc as we were doing all this we noticed that in the %appdata% thing there are no folders, well i think there might be 2, but the bin  resources saves screenshot etc are missing.

Everything is up to date please help.