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I tried to have a fresh install of latest Ubuntu Desktop 14.04 in my laptop running on Windows 8 using USB iso image.

I am careful on all things like :

  1. BIOS settings - External USB Flash drive - 1st Priority etc.
  2. Tried Directly to BOOT from USB option as of advanced windows 8 option.

Still, I am facing the error

Operating System Not Found

Any suggestions, geeks.

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How did you put the ISO on the USB drive? –  Louis Matthijssen May 3 at 10:47
Sir, I put the ISO as a bootable one which contains folders & subfolders. –  Mohanraj Subramaniam May 4 at 15:22

1 Answer 1

The USB has problems booting under an EFI environment. Usually, this results in a simple GRUB prompt. What you may try doing instead is enabling the CSM of your EFI (System/BIOS setup). On mine (Lenovo), this is an option called something like "Boot mode" with the options of UEFI and Legacy. In my case, I would change this to Legacy. Then, your USB should be able to boot depending on how you made the USB in the first place (i.e. unetbootin doesn't work).

However, since the install will be from Legacy mode, it will then only be bootable in Legacy mode, meaning you won't be able to boot Win 8.

In order to fix this, you have to enable EFI boot in Ubuntu after installation:

  1. From a terminal: sudo apt-get install grub-efi
  2. Reboot, change the UEFI (BIOS) back to UEFI mode (as opposed to Legacy)
  3. You should then be presented with a menu allowing you to boot several options including Ubuntu and Windows
  4. A few buggy UEFI implementations can cause issues. If you run into any problems, I can try to guide you form there.

OK, so it appears that you must have installed Ubuntu in legacy (non-UEFI mode). In order to fix this, follow these steps:

  1. Boot up Ubuntu from Legacy (non-UEFI) mode.
  2. From a terminal: sudo apt-get install grub-efi
  3. Reboot and enter Setup ("BIOS") via F1, Delete, F12, etc.
  4. Go to the "Boot" tab and move "Ubuntu" to the top.
  5. Reboot and you should see the GRUB menu with options for Ubuntu as well as Windows.
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Hello Githlar sir, I followed all things upto step 3. When I restart, two things happen. First one, If UEFI mode,Ubuntu is not showing in grub. Second one, if in legacy mode, Windows is not showing in grub. How to resolve to display both ubuntu & windows in UEFI mode,then to select as our wish? –  Mohanraj Subramaniam May 4 at 17:00
I updated my answer. –  Githlar May 4 at 20:36

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