If you’re getting Error Code 126 – Failed to Load onlinefix64.dll, it usually means the file is being blocked, quarantined, or doesn’t have the required permissions. This commonly happens due to Windows Defender or antivirus interference.
Below are three effective solutions to fix the issue.
Solution 1: Run the Game as Administrator
First, locate your game executable or launcher.
In this example, the issue occurs with GTA 5, but the same steps apply to other games.
Right-click the game launcher or executable and select Properties.
Go to the Compatibility tab.
Check Run this program as administrator.
Click Apply, then OK.
Now launch the game and check if the error is resolved.
Solution 2: Disable Microsoft Defender via Group Policy Editor
If the issue persists, Windows Defender may be blocking onlinefix64.dll.
Press Windows + S, type gpedit.msc, and press Enter.
This opens the Group Policy Editor.
Navigate to:
Computer Configuration → Administrative Templates → Windows Components → Microsoft Defender Antivirus
Double-click Turn off Microsoft Defender Antivirus.
Select Enabled, then click Apply and OK.
Close the editor and restart your PC.
⚠️ Note: This option is available only on Windows Pro, Enterprise, and Education editions.
Solution 3: Restore onlinefix64.dll from Windows Security
If Defender already quarantined the file, you’ll need to restore it.
Open Windows Settings.
Go to Update & Security → Windows Security.
Click Virus & threat protection.
Select Manage settings and temporarily turn off Real-time protection.
Now go back to Virus & threat protection and open Protection history.
Click Filter and select Quarantined items.
If you see onlinefix64.dll in the list, select it and click Restore.
After restoring the file, restart your PC and launch the game again.
Conclusion:
- Error Code 126 is usually caused by antivirus blocking
onlinefix64.dll - Run the game as administrator first
- Disable Microsoft Defender if necessary
- Restore the DLL file from quarantine if it was removed
