If nothing works, you need a deep wipe. Uninstalling via Steam leaves config files behind.

The "Tampering Detected" error in Age of Empires II: Definitive Edition typically triggers when an external process—most commonly , firewalls , or game overlays —interacts with the game's memory or files in a way the anti-cheat system deems suspicious . This error can grey out all menu options or crash the game mid-match. Common Causes