I see the error "Game failed to start (error code 51)" when launching a game through Steam. What can I do?
This issue can be caused by various background applications interfering with Steam. Please follow the steps found in the Programs Which May Interfere with Steam article before trying anything else.
This issue can be caused by an application called Airfoil. Airfoil is used to re-route audio from computer applications to wireless devices. Airfoil uses a feature called Instant Hijack which may interfere with Steam.
To disable this feature, do the following:
Alternatively, you can add Steam and any games you wish to play to the Exclude List, also found on the Extras tab in the Airfoil Preferences window. If the issue persists, it may be necessary to fully uninstall Airfoil.
F-Secure uses a feature called DeepGuard which may interfere with Steam. If you are seeing the above error, disable DeepGuard and re-test the issue. If the issue continues, you may need to *temporarily* uninstall F-Secure to determine the cause of the problem.