Game crash when im in Dalaran every time

I am so tired of this... i can not enter this damned city without gettin a crash, and having to wait for my char to log out... How can i fix this problem? What is the cause? My pc is so overpowered for this game i could probably run 10 simultaineous copies open but then this... Can you help me?

Apply Large Address Aware to wow.exe.

I have downloaded it and i have enabled my wow.exe to use more than 2 GB of memory. It didn't change anything.

UPDATE: I had to disable "read only" in properties of wow.exe and now it worked! :) Thanks a ton Pal! :D