This guide provides a definitive, fix. We won’t just solve the error; we will optimize the game to run smoother, look sharper, and never lock you out again. Part 1: Understanding the Error (Why "Must Be Running" Appears) Before smashing your keyboard, understand why this happens. DmC: Devil May Cry uses an older DRM (Digital Rights Management) wrapper called CEG (Custom Executable Generation), proprietary to Steam.
If you are a fan of stylish hack-and-slash action, you’ve likely encountered a frustrating roadblock when trying to launch DmC: Devil May Cry (the 2013 reboot) on Steam. Nothing kills the mood before a demon-hunting spree quite like the dreaded error message: "Steam must be running to play this game." Even worse? You are running Steam. You’re online, your friends list is active, and every other game launches fine. This anomaly, often coupled with performance dips and resolution scaling issues, has plagued players for years. This guide provides a definitive, fix
bInitializeShadersOnDemand=False AllowD3D10=False UseVSync=False SmoothFrameRate=FALSE Under [SystemSettings] , paste this for visuals: DmC: Devil May Cry uses an older DRM