VAC showing "?????" values

well i inputted the correct adresses into the cheat engine but when i'm done it shows "?????" as value. Am i doing this correctly???

well if it says "??????" then that mean u didnt attack cheat engine to maple story in time b4 the gameguard came up.

when the u press viem memory it suppose be alot of numbers
.....if it doesnt then cheat engine is not attach to maple stroy..

i have a prob just a little after this,

i read in a tutorial all u gotta do it click and change value ?? to 0

did it wrong.