Maplestory, how do i change the DEP settings?

ok so i just downloaded maplestory on laptop. i have windows vista. everytime i go on maplestory, it only lasts about 2 minutes...and then it exits and says something like "you have been disconnected from the login" or something like that. so i tried to change the DEP(data execution prevention) settings but im still stuck on the last step. when you add the ones you dont want DEP to work on...well lets just say i cant find maplestory? so can you please tell me how i find the maplestory file and all (if) the other files i should do as well? thanks so much!