UEFI only boots to Windows

[soundofthunder]

@heebo1974

My problem is that if try to boot with uefi it only boots Windows.

@heebo1974

I don’t quite understand why UEFI_OS and Linux Boot Manager boots now to Windows.

This is your Windows disk. Very obvious is the fact that it doesn’t show an $ESP; this disk is a BIOS/MBR type disk installed as Legacy;

@heebo1974

Device         Start       End   Sectors   Size Type
/dev/sdb1       2048     34815     32768    16M Microsoft reserved
/dev/sdb2      34816 248745983 248711168 118,6G Microsoft basic data
/dev/sdb3  248745984 250066943   1320960   645M Windows recovery environment

Whereas the Manjaro disk does have an $ESP; it is a UEFI/GPT type disk clearly installed using UEFI technology:

@heebo1974

Device             Start       End   Sectors   Size Type
/dev/nvme0n1p1      4096    618495    614400   300M EFI System
/dev/nvme0n1p2    618496 958313126 957694631 456,7G Linux filesystem
/dev/nvme0n1p3 958313127 976768064  18454938   8,8G Linux swap

@linux-aarhus

The confusion has to do with a mix of EFI and BIOS installations.

Those two cannot be mixed into the GRUB loader.

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@Wollie

At the end, best would be most likely to reinstall all what is currently installed in BIOS mode. Then grub in combination with os-prober should be able to manage the boot process.

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The following is a tutorial which illustrates general methods to avoid situations such as this when multibooting Linux and Windows.

Regards.

[Multiboot] Windows and Linux on Separate Disks

Multiboot Windows and Linux …on Separate Disks Firstly, this guide is intended for multibooting with each OS on a separate disk. If you have a laptop with only one disk, or If you wish to install an OS on it’s own partition on the same disk, this guide is not for you (but read on regardless, if interested). Secondly, this guide assumes each OS will be installed using UEFI and not UEFI’s CSM or Legacy mode. This guide does not support the traditional BIOS boot method. Additionally, all disks …