Grub is the best knwon boot loader. The first step is always to chroot into the installed system. See Chroot from Live System
Manjaro comes with some tools that ease this task.
pamac install manjaro-tools-base manjaro-chroot -a #grub-probe: error: cannot find a GRUB drive for /dev/sdb1. Check your device.map. #grub-probe: error: cannot find a GRUB drive for /dev/sdb1. Check your device.map. #==> Mounting (ManjaroLinux) [/dev/nvme0n1p5] # --> mount: [/mnt] # --> mount: [/mnt/boot/efi] # Changed to installed system pacman -Syu grub #[...] #Packages (1) install-grub-2:2.12-3 # #Total Download Size: 0.01 MiB #Total Installed Size: 0.01 MiB # #:: Proceed with installation? [Y/n] y #[...] # EFI system grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=manjaro --recheck #Installing for x86_64-efi platform. #Installation finished. No error reported. grub-mkconfig -o /boot/grub/grub.cfg #Generating grub configuration file ... #Found theme: /usr/share/grub/themes/manjaro/theme.txt #Found linux image: /boot/vmlinuz-6.6-x86_64 #Found initrd image: /boot/amd-ucode.img /boot/initramfs-6.6-x86_64.img #[...] exit
Find the system.
sudo wipefs /dev/nvme0n1p5 # DEVICE OFFSET TYPE UUID LABEL # nvme0n1p5 0x438 ext4 3899a753-aaaa-46e0-b034-cccccccccccc sudo mount /dev/nvme0n1p5 /mnt
Mount special filesystems:
sudo mount -t proc proc /mnt/proc sudo mount -t sysfs /sys /mnt/sys sudo mount --bind /dev /mnt/dev sudo mount --bind /dev/pts /mnt/dev/pts
Change into the installed system:
chroot /mnt
Try update grub. Then use the grub install tools:
# EFI system grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=manjaro --recheck #Installing for x86_64-efi platform. #Installation finished. No error reported. grub-mkconfig -o /boot/grub/grub.cfg #Generating grub configuration file ... #Found theme: /usr/share/grub/themes/manjaro/theme.txt #Found linux image: /boot/vmlinuz-6.6-x86_64 #Found initrd image: /boot/amd-ucode.img /boot/initramfs-6.6-x86_64.img #[...] exit
Unmount the installed system:
sudo umount -r /mnt/dev sudo umount -r /mnt/dev/pts sudo umount -r /mnt/proc sudo umount -r /mnt/sys sudo umount -r /mnt