How to fix
Invalid Signature Detected
on Windows

Hello, I was trying to update my Windows OS, and after it, my PC crashed, and I received the "Secure boot violation - invalid signature detected" error. Now all I see is a black screen which claims that I need some CD. I have no idea what is this and how to fix it, so I hope you guys could help me? My laptop is ASUS X550VX-MH71, and I am running Windows 10 if that helps.

Invalid Signature Detected error is not exclusive to Asus computers only and has been around for many years now. According to the error, the system cannot be booted because of invalid signature that relates to security policy. Most users who are not tech-savvy usually panic because they are unable to boot Windows as usual and consider the computer even broken. All they see is a UEFI of BIOS screen[ref en-1] which states the following:

Secure Boot Violation

Invalid signature detected. Check Secure Boot Policy in Setup

Ok

However, there is no need to be scared, as there are several ways to fix Invalid Signature Detected error without contacting tech support services or bringing the laptop the repair shop - these services are usually pretty pricey. In this article, we will provide you ways to fix "Secure boot violation - invalid signature detected" error by using a simple step-by-step guide.

The initial Invalid Signature Detected problem started with Windows 7 when Asus users applied the KB3133977 update. Initially, the patch was designed to prevent the encryption of drives on Windows 7 machines. While it fixes the problem, it causes a different issue to Asus computers, and users started seeing the Invalid Signature Detected error. The new issue was patched by Microsoft, but the error still prevails even in later versions of the OS.

There are several other reasons why users encounter Secure boot violation - Invalid Signature Detected error. For example, when running the double OS, when upgrading to Windows 10, after resetting BIOS to factory settings or connecting a new hard drive (HDD) or a solid-state drive[ref en-2] (SSD), etc.

To prevent such problems in the future, we highly recommend using [d1] - the PC repair software that can also fix the existing issues on all versions of Windows.

So now, let's proceed with the Secure boot violation - invalid signature detected error fix - please follow the steps carefully.

Step 1. Enter BIOS of your device

To fix the Invalid Signature Detected error, you will have to enter BIOS of your laptop of the PC. BIOS is a firmware[ref en-3] configuration of the computer and handles hardware initialization process during the boot. Ways to enter the mode varies from machine to machine, but in most cases, you should be able to enter it by restarting the computer and then continually pressing F1, F2, Fn + F2 or Del key. 

Nevertheless, you should be directed to the BIOS screen as soon as you press Ok on the error button window.

Step 2. Disable Secure Boot Control

• From the main tab, navigate to Security tab by pressing →
• Now press ↓ to reach Secure Boot menu
• Press Enter
• Select Secure Boot Control and then follow up by Disabled

  

Note: If you can see OS type option in this menu, make sure you set it to Other OS, even if you have Windows OS installed.

Step 3. Enable CSM and disable Fast Boot

• From Security tab go back up and select the Boot tab
• Select Fast Boot and hit Enter, then choose Disable
• Then pick Launch CSM and pick Enabled

  

• Now, navigate to Save & Exit tab
• Select Save Changes and Exit and confirm with Yes

  

Step 4. Enter Key management

If the previous steps did not solve your problem, the reason for Invalid Signature Detected error is the update performed on the UEFI/BIOS. To fix the issue, you will have to reset the keys.

• In the Bios, go back to Security tab
• Select Key Management
• Set all the keys to NOT INSTALLED