@XaCtLii, try verifying the integrity of the game cache. This will make sure that the game files are correct and not corrupt.

If that does not help then upload launcher logs, explain step-by-step what you are doing to start the game, and what the game does when you try to start it.

For issue with the launcher, you can export all launcher logs to the desktop via an action available in the option menu in the upper right corner (gear icon)

Hi! I have just purchased ARMA 3 and i too am having issues starting the game. i have attached the ARMAreport