how do i fix this error arma2oa.cfg.3D_performance

hi guys everytime i log on to play dayz i get this error it says No entry 'C:\Users\Rick\Documents\ArmA2\Arma2OA\ArmA2OA.cfg .3D_Performance

Could someone please help me with this.

Open the file C:\Users\Rick\Documents\ArmA2\Arma2OA\ArmA2OA.cfg notepad and add the following lines to the bottom:
3D_Performance=100000;
adapter=-1;