Blue Screening

So I'm running the 32-bit version of Windows 7. When I installed the game I went about the process of replacing the gameguard.des file in the Spellborn/Client folder. This originally did not work, so I also replaced the .des file in the Spellborn/Client/Game_Guard folder. This allowed me to run the game.

However, the next day when I tried to run the game it crashed my PC, giving me a blue screen. It did this repeatedly, and I had changed nothing in the Spellborn folder. I played around a little, reverting back to the old .des files, deleting the Game Guard folder and letting it redownload all the files etc. Eventually I got the game to work again. Truth be told, I'm not sure exactly what was the issue, as I landed up with exactly the same file setup as I had when the game was working.

Then, the following day, upon starting the game it crashed my PC again. It's doing this repeatedly. Does anyone have any idea what the issue is? I've followed the various guides available and nothing seems to work. It works and then just randomly stops working again.