if the game isnt running after pressing the "Play" button,download these files and copy them to your GTA IV main directory, http://www.gtavision.com/index.php?section=downloads&site=do&DLID=2914 NOTE: please copy those files after downloading,and replace them with any files from the same kind. if this helped you please tick this post as answerd or solved by pressing answerd in the bottom right of the post