Game deleted and cant re-install

I logged off the game yesterday for about a hour and just let my computer go to the screen saver and i came back and the game was un installed nobody else was on my computer there was no sign of it being deleted by recycling bin or desktop i cant access the game or anything,i tried re-installing and it said the file that was being copied was corrupted it was rez/REZ017 and it wont re-install is this is a problem with the game or just my computer?