hello, i have a macbook pro and i first installed a cad 2015 version from autodesk. after some time it stopped working and gave me an error box which said "A DISPLAY DRIVER FILE IS MISSING OR HAS BEEN CORRUPTED. THE PROGRAM WILL BE CLOSED". I then reinstalled my ios and got a crack version installed in it. but then that keeps doing the same now and then. i have reinstalled my ios THRICE!! pls urgent help needed