If you install Ubuntu, then Windows in a different partition, the GRUB boot loader vanishes. But don’t panic and reinstall Ubuntu — you can recover it.
Boot to the Ubuntu Live CD, open up a Console window and type:
# Create a directory called “mounted”: mkdir mounted # In there, mount the partition where Ubuntu is installed: sudo mount /dev/sda2 mounted # (For the above step you need to find the partition name on your own.) # However, replace the /dev directory in the mounted partition with the # current /dev directory: sudo mount –bind /dev mounted/dev # Change the root for now sudo chroot mounted # Finally, install grub to the first SATA disk: sudo grub-install –recheck /dev/sda
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