Missing or corrupted game files—especially the steam_api.dll file responsible for communicating with your client—will instantly trigger this launch error. Steam can scan your local directory and replace broken files automatically. Open your and locate DmC: Devil May Cry . Right-click the game title and select Properties .
Temporarily disable your firewall to see if it resolves the issue. Reinstall/Update Steam Client Missing or corrupted game files—especially the steam_api
How to Fix the "Steam Must Be Running to Play This Game" Error in DmC: Devil May Cry Missing or corrupted game files—especially the steam_api
Method 5: Add an Exception to Antivirus and Windows Defender Missing or corrupted game files—especially the steam_api