Go back to and click Manage settings .
This error happens when the critical Dynamic Link Library (DLL) component that bridges your game and the Steam platform goes missing, gets corrupted, or gets blocked by security software. Below is a complete, verified step-by-step guide to resolving the issue and getting your game running smoothly.
Click on the action, verify it mentions steamapi64r.dll or your Black Ops 3 folder, click , and select Restore . Step 2: Add an Exclusion to Prevent Future Deletion
Sometimes the issue lies within the Steam client itself, not the game. Reinstalling Steam can fix issues with the steam_api64.dll file location. Close .
Add the Black Ops III folder to your antivirus . Manually Reinstall the Steam Client Go back to and click Manage settings
Look for a recent block or quarantine event labeled as a "Severe" or "High" threat targeting your Black Ops 3 installation folder. Click on the action dropdown menu and select .
Download the latest installer from the official Steam website and reinstall it.
Security software frequently flags unofficial DLLs as threats, such as potentially unwanted programs (PUP) or trojans, and automatically quarantines or deletes them.
: This can repair underlying Windows system errors that might be affecting DLL registration. Open Command Prompt as an administrator. Type sfc /scannow and press Enter . Click on the action, verify it mentions steamapi64r
Check integrity of mods / third-party overlays
Open your Antivirus software (e.g., Avast, McAfee, Norton) or .
These files are often outdated, incompatible, or bundled with .
Select and then Exclusion (or "Allow") to prevent future deletion. Verify Integrity of Game Files Method 3: Install Visual C++ Redistributables
Click , select Folder , and choose your main Call of Duty Black Ops III directory to prevent future deletions.
Navigate to the _CommonRedist folder inside your Black Ops III installation directory. Run the installers for and vcredist .
Antivirus programs frequently flag cracked or even modified Steam DLL files as false positives. If your security software recently ran a scan, it likely quarantined the file. Open (Press Win + I ). Navigate to Privacy & Security > Windows Security . Click on Virus & threat protection . Select Protection history .
Here are the most effective solutions, ranging from simple checks to more advanced troubleshooting.
Scroll down to "Exclusions" and click . Click Add an exclusion and choose Folder . Select your Black Ops 3 installation folder. Summary Checklist ✅ Check Quarantine: Restore file if quarantined. ✅ Verify Files: Use Steam to fix missing files. ✅ Reinstall Game: Clean install to replace files. ✅ Update Drivers: Ensure graphics drivers are updated.
To prevent it from happening again, add your Black Ops 3 installation folder to your Exclusions or whitelist. Method 3: Install Visual C++ Redistributables