fdisk /dev/sda # Use 'a' to toggle active flag on the correct partition
# Mount root partition mount /dev/sda1 /mnt # Reinstall GRUB grub-install --root-directory=/mnt /dev/sda update-grub Using fdisk (Linux): active partition recovery full
# Linux fdisk -l /dev/sda diskpart list disk list partition fdisk /dev/sda # Use 'a' to toggle active
chkdsk C: /f /r
bootrec /fixmbr # Rewrites MBR code (does not modify partition table) bootrec /fixboot # Writes new boot sector onto the system partition bootrec /rebuildbcd # Rebuilds Boot Configuration Database check for file system corruption:
From Windows PE command prompt:
diskpart select disk 0 select partition 1 active exit After restoring structure, check for file system corruption: