The "Fatal Error" in Ace Combat 7: Skies Unknown is a common Unreal Engine 4 crash that typically occurs on startup or during high-intensity missions. As of 2026, the most effective solutions involve addressing audio sample rates, driver conflicts, and administrative permissions. Core Troubleshooting Steps

High Performance Mode

: In Windows Settings, set AceCombat7.exe to "High Performance" under Graphics Settings .

Remove Graphics Mods

: Specific mods, such as the "Ace Combat 7 Skies Unknown Graphics Mod" or certain F-35C modifications, are known to "brick" the game and trigger this error. Uninstall any visual or gameplay mods and reinstall the game if necessary.

Causes of the Fatal Error