I installed Ubuntu 12.04 as a dual boot, but I'm having trouble getting it to start. I just ran it off a live USB and installed it like that, using the Install Ubuntu alongside Windows option and just followed the prompts to install Ubuntu 12.04.

When I start the computer I get to the GRUB boot menu screen and select Ubuntu, but it just goes to a black screen. The only thing I can do from here is to press Ctrl+Alt+Del to reboot it, but it just keeps happening over and over. It also happens if I select the Windows or Ubuntu (recovery mode) options from the GRUB boot menu.

  • What method did you use to install Ubuntu? – BiggJJ Jun 28 '13 at 9:00
  • I just ran it off a USB and installed it like that, using the 'alongside windows' option and just followed the prompts – lexic Jun 30 '13 at 6:38

Try repairing the GRUB bootloader with Boot Repair. Boot to an Ubuntu live session from the live USB/DVD that you used to install Ubuntu. While running an Ubuntu live session open the terminal and type:

sudo add-apt-repository ppa:yannubuntu/boot-repair  
sudo apt update  
sudo apt install -y boot-repair
sudo boot-repair  

Open the Boot Repair application and select Advanced Options -> Main Options tab -> check Reinstall GRUB and Unhide boot menu as shown in the below screenshot. Click the Apply button. Then reboot the computer with sudo reboot

enter image description here

If the OSs were installed in different modes, dual booting Windows and Ubuntu can't work. If your Windows is installed in BIOS mode, it is recommended to install your Ubuntu in BIOS mode, but if it's installed in UEFI mode, then do the same with Ubuntu.

enter image description here
          BIOS vs. UEFI

To check whether your computer has UEFI or BIOS firmware open the terminal and type dmesg | grep "EFI v"

  • This will return a line like this, if the system was booted from EFI:

    [ 0.000000] EFI v2.00 by Lenovo
  • Or it will return nothing if it was booted from BIOS.

If you have installed Ubuntu in legacy mode on the same drive with GPT partitioning, you can use Boot Repair's Advanced options to uninstall grub-pc and install grub-efi-amd64. That converts the Ubuntu installation from BIOS boot to UEFI boot, the same firmware as most recently manufactured laptops with Windows pre-installed have.

Converting Ubuntu into UEFI mode

  1. Start Boot-Repair, and select Advanced options -> GRUB location tab.
  2. If you do not see a Separate /boot/efi partition option, this means that your PC does not have any UEFI partition.
  3. If you see a Separate /boot/efi partition option, put a checkmark in the checkbox to the left of it, then click the Apply button in the lower right corner.

    enter image description here

  4. Set up your BIOS so that it boots the hard drive in UEFI mode. The way to adjust this setting depends on the specific model of the computer, but generally this setting is located in the boot priority settings under the Boot tab of the BIOS/UEFI setup utility.

For more information about converting Ubuntu into UEFI mode review https://help.ubuntu.com/community/UEFI in the section about Converting Ubuntu into UEFI mode.

The grub bootloader can also be converted in the opposite direction from UEFI to BIOS. Linux can boot fine from a GPT disk in BIOS mode. See this answer: Convert from EFI to BIOS boot


Boot into a live CD and run this code:

sudo apt-get install boot-repair
sudo boot-repair

Choose the recommended repair and follow the instructions you are given. Once boot-repair is done, reboot and see if Ubuntu starts correctly.


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