Fixing Operating System Loader has no Signature Error

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You cannot start your PC because of the error message “Operating System Loader Has no Signature”. Not compatible with SecureBoot. All bootable devices have failed “Secure Boot Verification”? I understand that this error message is quite frustrating, but rest assured that we will resolve it. This article contains a step-by-step guide to correct this error.

If your operating system does not pass the secure boot check, its boot loader has been corrupted or maliciously modified. You can try going to your BIOS configuration (press F2 several times immediately after turning on the system) and disable Secure Boot to see if it allows your system to boot, but if it does, it means your boot loader is compromised, and of course, I don’t recommend using a system that has been compromised. If it does not start even if Secure Boot is disabled, something else has gone wrong.

How to solve the problem with the Dell laptop: The operating system charger signature was not found.

To solve the problem with the “Operating System Loader signature not found”, you must boot your PC from a Windows 10 USB installation media. If you do not have Windows USB installation support, you can create one (from another work PC) using the support creation tool.

Checking BIOS settings


One, when you take off, press F12.

2. reset the default bios settings

3. restart the laptop computer

4. in Bios, select the Boot Sequence menu.

5. manually add an additional line called “Windows Boot Manager”.

6. select /EFI/BOOT/BOOTX64.EFI.

7. exit

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Hard Reset

Disconnect all external devices, try to disconnect all devices from your computer. The only devices you need to leave connected to your computer are your screen, mouse and keyboard, if the computer is a desktop. Now turn off your desk and unplug the power cord from the desk.

In the case of a laptop, disconnect the charger and remove the battery if necessary.

Hold the power switch down for about 15 to 20 seconds, then reconnect the power cord at the office, reconnect the battery and charger in the case of a laptop, and start the system. In most cases, a hardware reset solves the problem.

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