Day One FixesKnown issueFixUpdated · 6 replies on Steam
Horizon Walker Suddenly Fails to Launch - Error 0x11C7 (Workarounds)
Short answer
Suggested fix (unconfirmed): Turn off Windows Smart App Control or add an exclusion for `HorizonWalker.exe` in your Windows security settings.
The problem
Title: Horizon Walker suddenly fails to launch — Error 0x11C7 Hello, developers. I previously played Horizon Walker successfully, but today the game suddenly stopped launching. When I click Play on Steam, it briefly shows “Launching” and then returns to the green Play button. I receive this error: “An application control policy has blocked this file.” (Error 0x11C7) I checked Windows Event…
What players suggest
Hello there, had a somewhat similar issue today, I do play on Linux so not sure if it is the exact same issue as you but I did manage to fix it. -First try the obvious, Verify Game Integrity: Right-click the game in Steam library, select Properties > Installed Files > Verify integrity of game files . -The other option is a little more risky specially if your account is not linked to your steam…
Concerning "error 0x11C7" that seems to be more of a window security issue Thanks for confirming. I agree that this seems to be a Windows security issue. Since the game worked before and now Windows Code Integrity blocks HorizonWalker.exe (Event ID 3077), I hope the developers can investigate the executable's signing or compatibility with Windows 11 Smart App Control.
Did you update Windows recently? They did release that 26H2 update that seem to cause numerous problems for users.
Did this work for you?
Source: original Steam Community discussion. Quotes are shortened; all credit goes to the posters.