I recently upgraded from Win8 to Win10. The Win8 machine was in a dual boot with Ubuntu on an 80GB SSD. After the update and a few other issues I created while messing around with GRUB, I'm now left with only one partition on the drive: the Win10 OS partition. That's it! And... it doesn't boot... and I think that's because it's all alone without an EFI boot partition and MSR...??? At least that's what this and this have to say.

I've attempted a few times following several different guides to reinstate the other partitions I've read (http://technet.microsoft.com/en-us/library/hh824839.aspx) are necessary to boot Windows. But it still refuses to boot. I'm confident this can be done but I'm struggling with the how.

I have full access to Xubuntu via LiveDisk. I can access the Win10 partition from the LiveDisk. And while I apparently don't have enough rep to post it, I can provide a pretty screen grab from gparted showing the current state of my disk.


You create a EFI System Partition (at least 100MB) with any tool (also from Linux) and a MSR partition (exactly 128MB). These two partitions preferably at beginning of disk (if there is free space).

Then boot from Windows 10 installation USB/DVD (you can download Windows 10 ISO from Microsoft if you don't have it and use some Linux tool to make Windows 10 installation DVD/USB).

Then Repair, Automatic Repair (eventually 2-3 runs with rebooting after each run).

  • What if automatic repair "can't fix" ? – deathangel908 Dec 23 '15 at 21:27
  • 4
    UEFI Boot can be fixed with a single command - "bcdboot.exe n:\windows" where n: drive is drive of not booting Windows. Offline sfc can fix damaged system files. – snayob Dec 24 '15 at 5:09
  • The one line command did it for me after creating the EFI partition – HarlemSquirrel Sep 30 '16 at 11:33
  • Some more info – Kevin Jul 16 '17 at 22:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.