Aggressive antivirus programs (like Avast, McAfee, or even Windows Defender’s "Controlled Folder Access") can quarantine the steam_api.dll file responsible for verifying your ownership.
Many players mod DmC to change character models or textures. However, some mods replace the game's executable file (DmC Devil May Cry.exe) or the Steam API file.
Title: FIXED: “DmC: Devil May Cry – Steam must be running to play this” error
Body:
If you’re getting the dreaded “Steam must be running to play this” message even when Steam is clearly open, don’t worry — it’s a common issue with DmC: Devil May Cry. Here’s what actually fixes it:
✅ 1. Launch from Steam, not a desktop shortcut
Right-click the game in your Steam Library → Play. Shortcuts sometimes bypass the Steam client check.
✅ 2. Run Steam as Administrator
Close Steam completely, right-click the Steam shortcut → Run as administrator, then launch DmC. Dmc Devil May Cry Steam Must Be Running To Play This
✅ 3. Verify game files
In Steam Library → right-click DmC → Properties → Installed Files → Verify integrity of game files.
✅ 4. Disable Steam overlay for this game
Properties → General → Uncheck “Enable Steam Overlay while in-game” — the overlay can conflict with the DRM check.
✅ 5. Reinstall Steam client service
Press Win + R, type steam://flushconfig (this resets Steam’s config without deleting games), then restart Steam. Aggressive antivirus programs (like Avast, McAfee, or even
🔁 If none work:
This error is usually due to a failed DRM handshake with Steam’s CEG (Custom Executable Generation). The steps above will force it to re-authenticate.
Hope this helps someone still slaying demons in 2025+! Step 4: Add the Steam folder as an exception as well