I have gotten this error a few times now, and I am not sure the cause of it. I have tried a uninstall and a reinstall, which I thought fixed it, but after getting the error again today... It is still there.

The most recent time this happened was when I was accepting a quest. I clicked the "accept button" and the quest text started to pop up, but the error message took over. When I finally got back into the game tonight, I tried to do the same quest and again I crashed. This time, however, there was no "Runtime Error" message. It just told me that the game has stopped working and closed down.