Repairing GRUB on Linux

Have you ever lost your GRUB loader because overwritten by Windows loader ? It's happen to me today, and I want to recovery it! It's not hard to do, you just need a Linux live CD/DVD to recovery your GRUB and these commands below. 

1. First, boot your live linux and open the terminal. 
2. Make sure you are login into root. If you're not, type sudo su and type your password . 
3. Type fdisk -l to show all your harddisk drive partition list. 
4. Search for your linux partition and remember it ! example my linux is at /dev/sda5
5. okay then. I should mount it, so type mount /dev/sda5/ /mnt
6. You should mount another system components by type this :
• mount --bind /dev/ /mnt/dev
• mount --bind /proc/ /mnt/proc
• mount --bind /sys/ /mnt/sys
7. Now, set your new root, type chroot /mnt
8. Type update-grub to check if my Windows loader is detected too. 
9. To install grub, type grub-install /dev/sda
10. Okay, thats all, now try to reboot your computer, type reboot.

Oh , i tried this scenario also ! I try to delete the /boot/grub folder and try to recovery it, simple, just type grub-install /dev/sda and it will be created again by GRUB. 

And it works perfectly on my computer, may it will help you someday.