ArchLinux Retore Grub - UEFI or Not

#loadkeys br-abnt2

# mount /dev/<root partition> /mnt

#arch-chroot /mnt

#nano /etc/default/grub

insert or uncomment

GRUB_DISABLE_OS_PROBER=false

save

(in UEFI case)

  #mount /dev/sda1 /boot/EFI #Mount FAT32 EFI partition

  #grub-install --target=x86_64-efi --bootloader-id=grub_uefi --recheck /dev/sda 

 (NOT in UEFI case)

    #grub-install /dev/sda

 

Regardless of your choice, execute:

 

#grub-mkconfig -o /boot/grub/grub.cfg

#umount -R /boot/EFI

#exit
#umount -R /mnt
#reboot