That error was likely due to the file playtime.dat having changed for some reason. It is a file that keeps track of how long you have been playing. If the file isnt there, the game creates it. If it is there, it reads the information about how much time you have played. If it gets changed by something else, it wont read correctly and can cause the game to break. A simple solution may have been to delete that file only. Just a hunch as I dont have acess to the game files right now.