Fix: Can’t Boot Windows 8, 10 After Installing Ubuntu

By: Marian Cularea
3 minute read

Most likely when you reinstalled your Ubuntu system on your Windows 8 or Windows 10 device you might of gotten some error messages when trying to boot into Windows 8 or Windows 10 operating system. Although this issue is not very common I will explain in a few rows below how you can fix it and prevent it from happening in the future.
unable to boot Windows 8, Windows 10 after ubuntu install
The error message that you might get is “no boot disk has been detected or the disk has failed” but you don’t need to be alarmed because in the majority of the cases your disk is not broken. The first step you should take is to check if you can boot into ubuntu, if you can then it is a Windows 8 or a Windows 10 issue and it can be resolved by following the tutorial posted in the lines below.

How to boot Windows 8 or Windows 10 after installing ubuntu

  1. Place a USB or a DVD in the Windows 8 or Windows 10 device with Windows recovery media.
  2. Reboot the Windows device and you should get to the “Advanced options” window.
  3. In the window that shows after the device boots from the USB or DVD you will need to left click on “Troubleshoot”.
  4. After left clicking on “Troubleshoot” you will need to select “Advanced Options” feature.
  5. Left click on “Command Prompt” feature.
  6. The Windows 8 or Windows 10 device will restart and then you will have to choose your account to sign in.
  7. Now after Windows restarts you will get to a black window which is the command prompt.
  8. In the command prompt window type “diskpart”.
  9. Hit “Enter” on the keyboard.
  10. Type in the following command “sel disk 0”.
  11. Hit “Enter” on the keyboard.
  12. In the command prompt type “list vol”
  13. Hit “Enter” on the keyboard.
  14. The EFI partition you have there should be a “FAT32” partition.
    Note: Depending on what volume your EFI partition is you will have to follow the next steps accordingly
  15. We will take for example that the “EFI” partition is Volume 2.
  16. Now type in the command prompt window “sel vol 2”
  17. Hit “Enter” on the keyboard.
  18. Type in the command prompt window “assign letter=a”
  19. After you hit “Enter” you will get a message saying “DisKPart successfully assigned the driver letter or mount point”.
  20. Type in the command prompt “exit”.
  21. Hit Enter on the keyboard.
  22. Now you will still have the command prompt window in front of you but you will be take out of the “DISKPART>” feature.
  23. Type in the command prompt window “cd /d a:\EFI\Microsoft\Boot\”
  24. Hit “Enter” on the keyboard.
  25. Type in the command prompt window “bootrec /fixboot”
  26. Hit “Enter” on the keyboard.
    Note: the bootrec /fixboot command will repair your selected drive.
  27. Now type in the command prompt window the following command “ren BCD BCD.old”
  28. Hit “Enter” on the keyboard.
  29. Type in the command prompt window “bcdboot c:\Windows /l en-us /s a: /f ALL”
  30. Hit “Enter” on the keyboard.
  31. Remove the USB or DVD with the recovery media and try a reboot of the Windows 8 or Windows 10 system.

After the restart everything should be back to normal and you should be able to boot into Windows with your ubuntu still running.
Please write us below for any questions that you may have on fixing your Windows 8 or Windows 10 to boot properly .

READ ALSO: How to Download More Cursors in Windows 8, Windows 10

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