Edit from last post::::: I know you probably know how to install optifine, as you are not dumb. But i will leave a set of basic instructions just incase you don't know, or to anyone else who has this error. 1: Download optifine (i'm going to be giving you the latest 1.8.1 version to see how it gets on for you) http://adf.ly/404181/optifine.net/adloadx?f=OptiFine_1.8.1_HD_U_C7.jar 2: Once downloaded (http://screencloud.net/v/1HZl) and you have the .jar file (http://screencloud.net/v/487x) open it up (http://screencloud.net/v/4Dy6) 4. Click "Install" (http://screencloud.net/v/7CDc) NOTE::::: IF IT COMES UP THIS (http://screencloud.net/v/8up2) JUST GO ON MINECRAFT LAUNCHER AND LAUNCH VERSION 1.8.1 SHOWN HERE - (http://screencloud.net/v/ufRs) and play, you can then close down minecraft and click install again. 5. You should get this message. (http://screencloud.net/v/aoTf) 6. Open up minecraft launcher and select version "Minecraft 1.8.1-Optifine_HD_U_C7 (http://screencloud.net/v/mcTs) 7. Save Profile (http://screencloud.net/v/n0LT) 8. Launch minecraft and hope for the best of luck. (http://screencloud.net/v/b9ff) (http://screencloud.net/v/3GmQ) Best of luck, hope this works for you. Report back if it still doesn't.