Os not found

[Saig39]

I tried to turn on secure boot, I went to bios and did legacy boot disabled and secure boot enabled. Now my laptop says operating system not found but it worked before. Please help me I'm in need of help

[BeemerBiker]

Please provide the Product ID or exact model name for better assistance. Preferably the full product ID including the characters after the # symbol. This code may be needed to find cloud recovery files.

If you disable secure boot does it work?

Windows 11?

Linux?

FreeDos?

[Paul_Tikkanen · Accepted solution]

@Saig39 

The problem you are experiencing is that your notebook has Windows installed in Legacy mode and it boots using the MBR partition scheme.

When you enabled secure boot, the notebook can only boot up with Windows installed in UEFI mode which uses the GPT partition scheme.

Go back and enable Legacy mode and the notebook should boot up again.

If you want to enable secure boot, you have two options:

1. Reinstall Windows in UEFI mode by booting your Windows installation media from the (U)EFI USB flash drive, not the legacy one.

2.  There are some YouTube videos out there that provide the guidance to convert from MBR to GPT without having to reinstall Windows.

Back up any files you don't want to lose before attempting the conversion.

Convert MBR to GPT without loss DATA | Windows 11/10

Convert MBR to GPT Without Loss Data in Windows 11 / 10 | How To Change mbr to gpt Without Reinstall

After you make the conversion, restart your PC, go into the BIOS, disable legacy mode/enable secure boot.