Grub and refind do not show Windows for dual boot

Hey there,

I am trying to use Manjaro as main operating system, while using Windows for gaming only.

So I used a 1TB SSD in my machine to install Manjaro on it. Windows remains on a M2 SSD.

Unfortunately I am not able to get grub or refind showing Windows.

I checked my Windows partition in Windows with the Disk Utility and its a GPT partition.

In Manjaro when using sudo fdisk -l the Windows partition is shown as dos

The os-prober doesnt show any entry.

Maybe someone has an idea. (read some topics here for a while but nothing worked) Windows boots fine through the motherboards UEFI.

I tried to add GRUB_DISABLE_OS_PROBER=false to the grub config… Doesnt do the trick either.

Currently I am booting via UEFI Boot Override ^^"

That is a signal that the Windows Bootlader works in BIOS (legacy) mode, although it shows in your UEFI, it can handle both modes: EFI and BIOS.

Then it must be a Hybrid-MBR partition table. It is GPT, but has an MBR overlay, therefore: BIOS and not EFI.

Err… Thats bad :smiley: is that fixable? Or do I have to reinstall?

Yes, that is fixable without reinstalling Windows, but you know this forum is for Manjaro, not Windows. So ask that in a Windows Forum of your choice or use a search engine.

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Fair. Thank you very much for pointing me to it @megavolt

Found the issue. Funny thing is tho (maybe interesting for others):
Windows does not show the Hybrid-MBR. It shows, that all is running perfectly with GPT.

Google for mbr2gpt there is a Microsoft Learn Site for using it. Conversion takes about 5 seconds.
Afterwards sudo update-grub to let it detect the “new” Windows entry.

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