I have no experience with that game, but you can try to see if there is an repair tool from the game. I assume it is an MMO.
You can also try updating your Nvidia graphics drivers.
Had an issue once when playing a game, that required me to either downgrade my graphics drivers to an certain version or wait till they patched the issue with the new one. I had no clue, but had to use trial and error.
Hope this helps, good luck.