How to Reinstall Grub When Ubuntu or Linux Mint Won’t Boot

repair, reinstall, restore grub

Grub 2, the Ubuntu and Linux Mint’s default bootloader typically gets overridden when you install Windows as a dual-boot OS. To make Ubuntu and its derivatives boot again, you need to reinstall (repair/restore) Grub using a bootable Ubuntu/LinuxMint CD or USB.

Typically you’ll get the following error boot screen:

error: no such partition.

grub rescue> _

Tutorial Objectives:

  • Reinstall Grub 2 when Ubuntu or Linux Mint won’t boot
  • Enjoy!

To get started, insert your Ubuntu USB into computer and boot up. When you’re in, follow the steps below to reinstall grub 2:

1. Open Gparted Partition Editor from Unity Dash to check out which partition your Ubuntu/Linux Mint system installed. It is usually a EXT4 Partition.

In my case, there’re 3 Ext4 partitions. We can check the user names on each partition after step 2 by command cd /mnt/ && ls home/

gparted partition editor

2. Press Ctrl+Alt+T on keyboard to open terminal. When it opens, run command below to mount the partition:

sudo mount /dev/sda7 /mnt

3. Now reinstall Grub2 via command below:

grub-install --root-directory=/mnt /dev/sda

If the installation is successful, you will get the similar output:

Installation finished. No error reported.

4. Finally update grub boot loader and done!

sudo update-grub