Ridiculous "Access Denied" Error

Alright, so I download the game and play for a while. Everything is great till I get a little impatient and decide to cheat (Sorry) So, I find this cheat that says if I change the sell back rate in the data section I can get a lot of easy cash. Well, I must have royally screwed up because when I start up the game a pop up that says “Please check publishers website for tech support Details: [SetDisplayMode]” Since I vaguely know what that means, I decide to uninstall and re-install hoping everything will reset itself and allow me to play the game again. Unfortunately, no. As the download finished I get a big “Access Denied” pop up. Not so much of a big deal since it already installed the game, except the game has that same pop up. Is there any way to fix this?