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I'm getting the following error

enter image description here

I followed instructions from this video: https://www.youtube.com/watch?v=GaCbTe1eEes

marked as duplicate by karel, Fabby, Kulfy, vidarlo, Eric Carvalho Jun 20 at 21:35

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  • 1
    listen, should use grub. there are stricly no advantages to using windows bootloader (as you can clearly experience right now) and all the advantages to using grub. If grub was doing something you didn't like (not putting windows first, showing up at all instead of booting straight to windows) then know that grub is incredibly customisable : doc.ubuntu-fr.org/grub-customizer and despite all these advantages it doesn't have to pay for it with speed, it's still faster than windows bootloader. could you please explain why you chose to follow this video guide? – tatsu Jun 13 at 9:26
  • Microsoft has required vendors to install Windows 10 in UEFI boot mode to gpt partitioned drives. So is this an upgrade from Windows 7 or did you install yourself in old BIOS boot mode? Grub4dos will not work with newer UEFI systems as all systems must boot in same boot mode once started. – oldfred Jun 13 at 13:35
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    @tatsu I followed that video because I did not know that it is possible to customize grub2 for showing windows first, – A.K. Jun 15 at 3:52
  • @oldfred I just followed the video to choose to boot from windows bootloader instead of grub2 and everything happened automatically,I did not upgrade my windows. – A.K. Jun 15 at 3:53

I would recomend booting back ontot the live USB you used to install ubuntu,

opening a terminal with these keystrokes: Ctrl+Alt+T and pasting this command into it :

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

this will fix your dual boot, putting back grub.

you'll be able to boot into both your windows and your ubuntu

later if you want to have windows show up first in the list (or any other change/enhancement), you can boot to your ubuntu, open a terminal again and run :

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer

you can then open grub customizer from your start menu. the rest is pretty intuitive.

there's mountains of evidence online to back the idea that grub (or systemd or any other) are supperior in every way to windows bootloader, starting with wikipedia :

  1. https://en.wikipedia.org/wiki/Comparison_of_boot_loaders
  2. https://www.quora.com/What-is-the-difference-between-GRUB-and-the-Windows-bootloader
  3. Grub or Windows Bootloader for Dual Boot?
  • 1
    Thank you so much. :) – A.K. Jun 13 at 13:23
  • you're very welcome! :) – tatsu Jun 15 at 12:26

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