Fix: EFI USB Device has Been Blocked by Security Policy
This problem is due to the Secure Boot feature from BIOS
- A secure boot feature or possibly corrupted BIOS can cause the EFI USB device has been blocked by the current security policy error on Windows PCs.
- Most of our readers have resolved this issue by disabling the Secure Boot feature from BIOS.
- Some users might need to restore setup defaults for the BIOS to fix the EFI USB device has been blocked error.
Users can utilize alternative platforms on their Windows PCs from bootable USB drives. However, some users see an EFI USB device has been blocked error when they try to boot from EFI USB devices.
Consequently, users can’t boot from or utilize EFI USB drive devices because of that error. You can resolve the EFI USB device has been blocked error in Windows 11/10 with the solutions below.
How come the EFI USB device has been blocked error arises?
The EFI USB device has been blocked error message says that a security policy has blocked the drive. To be more specific, a secure boot feature blocks the drive.
To fix the EFI USB device has been blocked error, you need to disable the Secure Boot feature. You’ll need to enter your PC’s BIOS (or UEFI firmware) from which you can disable that feature.
How can I fix the device has been blocked error in Windows 11?
1. Disable Secure Boot
1.1 Restart the UEFI Firmware settings
- Hold down the Windows key and press I to launch Settings.
- Click the System tab’s Recovery navigation option. You’ll need to select Update & Security and Recovery in Windows 10’s Settings app.
- Select the Restart now option to enter Advanced Startup.
- Then choose the Troubleshoot option.
- Select Advanced options, then select UEFI Firmware Settings.
- Click the UEFI firmware Restart option.
1.2 Disable the Secure Boot setting
- Select the Security (or a Boot) tab inside BIOS.
- Find and select the Secure Boot option with the keyboard.
- Press Enter to bring up a Disable option and select it.
- Next, press the F10 button to save and exit BIOS.
- Select Yes to confirm.
Some users may need to set an admin password to change the Secure Boot setting. If that option isn’t accessible, try selecting the Set Administrator Password option within the BIOS first.
2. Reset BIOS to default settings
- Enter your PC’s BIOS via Settings as outlined for the first fix or with a different method. Our how-to enter BIOS guide includes numerous methods for entering the BIOS on Windows PCs.
- Select the Exit tab in the BIOS.
- Press the F9 key to select the Load Default Settings option. Or select that option with the arrow keys and hit Enter.
- Then select Yes to confirm the selected option.
- Press the F10 key and select the Save option.
There aren’t many ways to fix the EFI USB device has been blocked error. However, the BIOS resolutions in this guide are widely confirmed to resolve that issue by users who have fixed it.
Bear in mind that BIOS interface layouts vary. So, it might also be a good idea to look up how to disable Secure Boot and reset the BIOS within a manufacturer guide for your specific PC model.
The manufacturer’s website for your PC model will likely include such guidelines.
Because this issue appeared while trying to boot from a USB stick, here’s our guide on how to create a Windows 11 bootable USB drive.
Did you manage to clear this problem? If you have any issues, feel free to use the comments section below.
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