Unable to launch Win10 without going through the BIOS

piloukou Posted messages 1 Status Membre -  
Malekal_morte- Posted messages 178136 Registration date   Status Modérateur, Contributeur sécurité Last intervention   -
Hello, I've been encountering a problem since a recent "attempt" to change my BIOS from legacy to UEFI. Since this modification, I can no longer boot my computer as it immediately launches a command shell prompt. Changing the "boot priority" in the BIOS isn't enough because when I select my SSD where Windows is installed, it doesn't work; the PC tells me it can't find a device to start Windows. Therefore, I have to go into the BIOS settings to override the boot sequence with Windows Boot Manager, and that works—Windows launches. Do you know what solutions exist to resolve this problem? A BIOS update? Thank you in advance.

Configuration: Windows / Chrome 79.0.3945.117

1 réponse

Malekal_morte- Posted messages 178136 Registration date   Status Modérateur, Contributeur sécurité Last intervention   24 711
 
Hello,

It's normal, your Windows 10 is installed in MBR.
So if you change the boot method, it won't boot anymore.
If you switch to legacy, it should work again.

You can convert your MBR disk to GPT without data loss.
This can be done from a Windows 10 installation USB drive.
See: MBR2GPT: converting an MBR disk to GPT.

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If you think everything is correct and your Windows 10 should work in UEFI then:

From a functioning computer: Use Media Creation on a valid computer to create a USB installation drive: https://www.microsoft.com/fr-fr/software-download/windows10
  • Boot from it by modifying the boot sequence and select the USB drive or DVD: How to boot the computer from USB drive
  • You will arrive at the Windows installation program.
  • Go to Repair your computer (menu at the bottom left on the main page)
  • Advanced options for troubleshooting
  • Command Prompt
  • type diskpart and press enter

Provide the output of the following commands:

list disk
sel disk 0
list partition
list volume
exit


Take a photo of the output and provide the result in a screenshot.

And provide the output of the command:
bcdedit /v


Take a photo of the output and provide the result in a screenshot.

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