Why wont combat arms work

Ok first thing to do is to go to the site and check the requirments and make sure your compuer meets them, second you should simply redownload it usually this solves the porblem. make sure you are starting it correctly; when starting it you should be clicking an icon with a soildeirs head and googles on him(double click it). Most of the time it asks you if you trust the program click allow(it possses no threat to your computer). Well that's it if it still doesn't work tell me i will help :)