Module Blocked from Loading into Local Security Authority: What Does It Mean and How to Fix It?

Question

What does the message "This module is blocked from loading into the Local Security Authority" mean, and what steps can be taken to resolve this issue?

Answer 1

Hello, korziox

Thank you for your feedback. In short, this message indicates that a Windows security feature is functioning properly. It informs you that Windows has successfully blocked a program module (a .dll file) that it deemed potentially unsafe or incompatible from loading into the system's most secure core area.

Here are some troubleshooting solutions:

 

Method 1: Repair or Reinstall the Software

If the update does not work or you are already using the latest version, you can try repairing or reinstalling the software.

Go to Windows Settings > Apps > Apps & features.

Locate Bonjour, iTunes, or iCloud in the list.

Click on it and select Modify (if a repair option is available) or Uninstall.

If you choose to uninstall, restart your computer after completion and reinstall the latest version from the Apple official website.

 

Method 2: If you don't need Bonjour, uninstall it

Many users install iTunes solely for managing their iPhone and do not require Bonjour's network discovery feature. If this applies to you, you can directly uninstall Bonjour.

Go to Settings > Apps > Apps & Features.

Locate Bonjour in the list.

Click it and select Uninstall.

Note: Uninstalling Bonjour may cause certain iTunes features (such as Home Sharing, Apple TV connection, and Wi-Fi sync) to become unavailable. If these features are important to you, do not use this method.

 

Method 3: Disable LSA protection

This is a last resort, as it reduces your system's security. Unless you are fully aware of what you are doing and are willing to take the risk, this method is not recommended.

Warning: Disabling LSA protection makes your system more vulnerable to attacks such as credential theft.

If you insist on proceeding, follow these steps:

Press the Win + R keys, type regedit, and press Enter to open the Registry Editor.

In the address bar at the top, paste the following path and press Enter: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa

In the right-hand window, locate a DWORD (32-bit) value named RunAsPPL.

If it is not found, right-click in the blank space on the right -> New -> DWORD (32-bit) Value, and name it RunAsPPL.

Double-click RunAsPPL and change the Value data to 0.

(1 or 2 enables protection, 0 disables it)

Click OK and close the Registry Editor.

Restart the computer for the settings to take effect.

I look forward to your feedback. 

Best Regards,
Ian Trinh | Microsoft Q&A Specialist