Install/Recover Grub from Linux Live CD

Install/Recover Grub2 from Linux Live CD/USB after installation of other Operating Systems (Windows xp, Vista, 7, 8) or Grub doesn't load

Recommended Live CD's (Ubuntu 12.04/11.10/11.04/10.10/10.04/9.10/9.04/Mint)
Recover/Reinstall/Repair grub2 from Linux Live CD/USB after Windows 7/8/vista/xp or grub doesn't work, It is really easy to install grub.
You just have to follow simple steps after that you will see grub2 in your system again.


First of all Boot your Linux Live CD/USB then open Terminal  and enter following commands:
This command for root permissions:

Terminal Command:
sudo -i

Check the drives number in Partition Manager :

Terminal Command:
sudo fdisk -l

Now select your Linux installed drive and change the number in following commands (Only change 'x' with your drive number) and change (sda) with your hard drive it can be (sdb, sdc, etc) you can see this in Partition Manager:

Terminal Commands:
sudo mount /dev/sdax /mnt
sudo mount /dev/sdax /mnt/boot
sudo mount --bind /dev /mnt/dev/

This command will change mnt directory permissions to root permissions:

Terminal Command:
sudo chroot /mnt

Now grub install command and Change 'a' in "sda" with your hard drive where you want to install grub, check in Partition Manager:

Terminal Command:
grub-install /dev/sda

Now installation finished, Enter following commands to unmount (If these two command doesn't work, then leave them):

Terminal Commands:
sudo umount /mnt/dev
sudo umount /mnt

Now reboot your pc:

Terminal Command:
sudo reboot

Your grub is back. That's it.