Possible Duplicate:
How can I repair grub? (How to get Ubuntu back after installing Windows?)

I have dual boot with Windows 7 And Ubuntu 11.10. Yesterday I tried installing Ubuntu 12.04 LTS from a CD.

But now, when restarting my PC I get this error:

error: no such device: 4cfe3cc0-370e-48ed-82cd-7cd2ca7a0414.
grub rescue >

I am not an experienced Ubuntu user and would appreciate any help since I can now no longer use my PC at all.


1 Answer 1


The easiest way to solve dual boot problems is to use Boot-Repair (IMHO).

What is Boot-Repair?

Boot-Repair is a simple tool to repair frequent boot issues you may encounter in Ubuntu like when you can't boot Ubuntu after installing Windows or another Linux distribution, or when you can't boot Windows after installing Ubuntu, or when GRUB is not displayed anymore, some upgrade breaks GRUB, etc.

Installation and use:

  • Boot into Ubuntu Live CD or USB
  • Hit Alt+Ctrl+T to open terminal and run following commands:

    sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
    sudo apt-get install -y boot-repair && boot-repair
  • Once done Boot-Repair will open with two options choose the first option (Recommended repair).

    enter image description here

  • When repair is finished, Save the URL that appeared, Then reboot.

    enter image description here

  • If the repair didn't succeed, Share the URL on askubuntu or any other help forum for more help.

  • 1
    I LOVE Boot Repair! It fixed my computer in less than 1 hour! May 18, 2012 at 22:29
  • 1
    I have this on a CD, and it has fixed problems a few times for me before I learned how to boot from GRUB and fix it myself. But I'd still use it if I can't get in from the GRUB prompt for some reason. May 19, 2012 at 3:17

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