: Open the EA app, click the menu (three lines), go to Help > App Recovery , and select Clear Cache . This often resolves "not installed" loops by resetting temporary files.
Open Origin first, go to the game folder, and run the fifa16.exe file directly rather than through the launcher. If that fails, verify your game files and run both Origin and the game as Administrators. fifa 16 origin not installed error fix pc link
This advanced method involves swapping your current game files with a known, clean set. It is a common practice in the modding community. : Open the EA app, click the menu