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I had two operating system on my computer.

I used os-uninstaller to remove window 8 from my computer, then I restarted my system but was unable to continue to Ubuntu and I get a message "no bootable device".

I tried to reinstall Windows but couldn't as it showed me that the partition can't be used because it is on NTFS.

Then I used a boot repair disk but the problem still exists. This is the boot info summary.

Zanna
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Mohamed Ahmed
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1 Answers1

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You have an UEFI system and UEFI install, but somehow converted the ESP - efi system partition sda2 from FAT32 to NTFS. It must be FAT32 with boot flag to be seen as ESP.

And now all references to ESP in fstab, grub, & UEFI are to now missing ESP. You will have to recreate ESP and at least a total reinstall of grub. The reinstall of grub can be done from Boot-Repair's advanced options.

https://help.ubuntu.com/community/Boot-Repair

https://sourceforge.net/p/boot-repair/home/Home/

Some brands of systems will only boot "Windows Boot Manager" as UEFI entry. That is a violation of UEFI standards, but it is by description only, so we can make booting Ubunutu's shimx64.efi have that description. You then boot Windows entry to actually boot Ubuntu. sdX is drive, Y is efi partition example for sda2

sudo efibootmgr -c -L "Windows Boot Manager" -l "\EFI\ubuntu\shimx64.efi" -d /dev/sda -p 2

man efibootmgr

http://askubuntu.com/questions/486752/dual-boot-win-8-ubuntu-loads-only-win/486789#486789

oldfred
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