I downloaded the client for Mist of pandaria last night. It takes a lot of time to open the login screen when on the client and once I log in it just shuts down.
In the "errors" floder I found this:

Exception handler died
Original exception:
0xC0000005 (ACCESS_VIOLATION) at 0023:106C269B
The instruction at "0x106C269B" referenced memory at "0x106C269B".
The memory could not be "executed".

Help? please?... I don't know what's going on.