Do you have Linux/Windows dual boot workstation? Have you ever found your GRUB installation overwritten by another Windows Update? If your workstation supports EFI boot loader there is an easy way to reinstall the grub from your Linux distribution. In case your workstation is non-EFI (legacy, older way of booting) see another post.

1. Get yourself another workstation.
2. Get eEFInd USB image. You’ll find it from the download page. Look for “A USB flash drive image file”.
3. Unzip the image package and write it to the USB memory:
   • Linux: Give following command where /dev/sdX points to your USB memory.

     sudo dd if=refind-flashdrive-0.8.6.img of=/dev/sdX bs=1M

   • Windows: Use Win 32 Disk Imager to write the image to the USB memory.
4. Boot the target workstation from rEFInd USB. It creates a nice boot menu for you. Select the option which looks most promising and give it a try.
5. After the successful boot reinstall grub:

   sudo grub-install

6. Reboot. Don’t forget to remove the USB memory.