Windows 10 upgrade kills grub and boot-repair doesn't help

I’ve just upgraded to Windows 10 from Windows 8.1 on my partitioned laptop that has Ubuntu 14.04 installed. Grub no longer appeared on boot so I ran boot-repair from an Ubuntu liveUSB. This didn’t seem to have any effect. I’ve checked and secure boot is still disabled.

Log from boot-repair:

So what’s next?

Update: I’ve attempted to use chroot to update grub from my Ubuntu partition. update-grub runs successfully finding both linux and windows boot manager but the process still doesn’t have any effect. grub-install complains that it cannot find EFI directory (but I have mounted everything correctly).

Update2: Just discovered that running efibootmgr after chroot into ubuntu shows ubuntu as not being in the boot order at all. I manually changed the order and rebooted to discover that the bootorder was reset. I run in windows: bcdedit /set {bootmgr} path EFIubuntushimx64.efi But this has no effect either even after reporting ‘Operation Successful’.

I just had to run this in Windows as an administrator:

bcdedit /set {bootmgr} path EFIubuntugrubx64.efi

Or, if you are using PowerShell:

bcdedit /set "{bootmgr}" path EFIubuntugrubx64.efi

GRUB appears fine on boot and I can boot into Ubuntu and Windows 10 fine.

As pointed out in the comments (by David Faure), the final argument to this command depends on your particular system configuration. You can use this command to determine the correct path for your system:

bcdedit /enum firmware

This will list all the installed boot managers and associated EFI paths, and grub should be somewhere in the list.

Note: This works without live USB’s, but you might need to boot into BIOS and turn off secure boot. This can stop the above from working.

Answered By: Nicholas Verstegen

I am not sure that is related but I also ran into a bit of an issue trying to upgrade to windows 10 from a windows 8.1/debian dual boot.

Basically, at some point in the upgrade, I ended up with grub going into rescue mode because my debian partition had been wiped in the process and hence the boot files with it (I generally have a separate boot partition but not this time …). From a look at this link: Windows 10 upgrade led to grub rescue

I think the problem is that windows did not write the partition table correctly during the upgrade process.

Anyhow, I fixed the problem by booting on a Win8.1 install external hdd and followed those instructions: (scroll down to win8/8.1). That wiped grub and reinstalled mSoft’s boot loader. I then managed to finish the upgrade and reinstalled debian all together since at the time I had not realised it was simply a problem with the partition table not being written correctly. Yet a better solution would be to try and recover your partition table (using testdisk?) and then reinstall/update grub.

Hope that helps.

PS: Thank you microsoft for not giving a damn about people who have a dual boot configuration …

Answered By: Jérémy Riviere

same problem here, upgrading from windows7 to 10 in a dual boot pc…
I resolved in this way:

  1. Upgrade Windows
  2. During installation process, after the first reboot, i get the grub rescue prompt, fixed this with BootRepair in a USB stick
  3. Completed the Windows installation, GRUB has gone and with a live cd of gparted i noticed that all partitions was still there but all of them were NTFS
  4. Used TestDisk from windows recovered my Linux partition
  5. BootRepair again and everything seems ok (i’ve Windows voice in GRUB menu duplicated.. i don’t know why, but everything seems ok to me now!)

I hope it can be useful to someone!

Answered By: Francesco

8/8/15 I upgraded from Windows 7 to Windows 10, and after Windows10 installed I made Firefox my default browser and shut down my PC, waited 15 seconds and powered up the PC and didn’t even expect that it would give me an option to still choose Ubuntu within 5 seconds.I clicked Ubuntu and it seemed to hang in limbo with a grey screen for what seemed an eternity , but I didn’t do anything except tapped the enter button on the keyboard to attempt get something to happen and waited , then finally the familiar black screen to choose Ubuntu or advanced options appeared. It booted up in Ubuntu fine. After I shut off and powered up in windows 10, the time and date in Windows showed 5 hours fast, just like windows 7 did after using Ubuntu, LOL. Next time I chose Ubuntu to boot the boot up wait was a lot shorter.

Answered By: James

I used the rescuetux/supergrubdisk. Booted it from DriveDroid on my android tablet. Then used auto detect rescuetux. Went into the WINDOWS button, hit the betaWindowsMBR repair button. And selected /dev/sda2 ok ok ok. Then it said successful. Now i just booted back into windows uefi menu.

Answered By: Beezy Weezy

My fix was close to @Francesco but a bit different.

  1. Upgrade Windows from 7 – 10.
  2. During installation process, after the first reboot, i get the grub rescue prompt, fixed this with BootRepair in a USB stick.
  3. Grub now appears, but is only showing Ubuntu partition, not Windows.
  4. Log into Ubuntu, go to terminal and type update-grub
  5. Now Windows shows back up in grub menu, continue with Windows 10 upgrade.
Answered By: Metropolis

For me the process was quite complicated. I use boot repair form the usb stick, and after I remove the usb stick and restart the computer only ubuntu login option came. I log into Ubuntu which was installed in my computer hard disk and then use boot repair again. After that when I restart my computer now I have the options to login into both Unbunt and winsows 10 and it’s working just fine.

Answered By: mr_azad

Have you checked the order of your boot sequence? If the Microsoft boot loader is at number 2, move it to the bottom and reboot.

You can check it from within Ubuntu by running sudo efibootmgr -v in terminal.

Answered By: Adam Elvin

My wife’s machine is older (non-UEFI) and had Ubuntu installed on a logical extended partition. Upgrading to Windows 10 first killed grub so reboots resulted in the “grub rescue” prompt, which I restored with BootRepair from LiveUSB, but my Linux partition was missing! I restored this with parted rescue from LiveUSB, which found and recovered the partition. From there, I mounted the partition from LiveUSB and did a grub-install and was able to boot back into the recovered Ubuntu and Win10. Hope this helps others.

Answered By: bheeshmar

If you have a Win10 installation media you may use this to install a new fresh MBR. Just boot intil you see “Install now” (or similar) but do not click on it. There is a small link saying “repair tools” (or something). From this you may enter command prompt.

cd c:windowssystem32
bootrec /fixmbr

maybe even

bootrec /fixboot

This should fix the issue. But, Your Linux is longe gone due to Microsofts ignorance to peoples own choices. They have just decided that it is okay for them to delete whatever is available on your HDD and which they do not like. Therefor we may legally decide that MS is a bunch of dorks…

Win10 installation media creator tool is freely available from

Answered By: 19Vidar75

After upgrading to Windows 10 on Acer Aspire-AXC-605, I could not boot into ubuntu and F2 key would not bring up bios screen so could not boot from USB ubuntu live.

I had to use Esc key while booting this brought up a “Diagnose PC” screen and I could boot USB from there.

Answered By: Geo

The only solution that worked for me is described on that link
I’ve brought it again here just because it’s easier to find this thread on google.

Essentially the steps are:

  1. Using Ubuntu Live to boot in ‘Try Ubuntu’ mode.
  2. Use GParted to verify the correct linux partition (e.g. /dev/sda2).
  3. Mount the linux partition:

    sudo mount /dev/sda2 /mnt  #Replace sda2 with your partition number
  4. Mount all other linux system folders :

    for i in /sys /proc /run /dev; do sudo mount --bind "$i" "/mnt$i"; done

    If you are running an UEFI system, you will also have to mount your EFI directory using the following command:

    sudo mount /dev/sda1 /mnt/boot/efi
  5. chroot into your install

    sudo chroot /mnt
  6. Now that you are logged in your installation (not the Ubuntu Live) just do

    grub-install /dev/sda
    sudo reboot

And that’s it !
Credits go do Scott Severance on the link I’ve mentioned above.

Answered By: Nir

We have a number of answers here providing steps on how they fixed the issue (Loss of Grub menu due to latest Win10 update). Various answers proves the solution isn’t unique as the machine configs ain’t unique.

For my system (Acer E5-575G-57D4), following is the fix:

Short answer:

1) In Windows, as mentioned by Nicholas in his answer, enter the following command as administrator in Windows command prompt.

bcdedit /set {bootmgr} path EFIubuntugrubx64.efi

2) Run boot-repair utility with Live Ubuntu CD/USB.

Long answer:

1) Log in to Windows.

2) Create a bootable USB stick (with your Ubuntu version) and plug it in.

3) Enter this command as administrator in command prompt:

bcdedit /set {bootmgr} path EFIubuntugrubx64.efi


4) While it boots press F12 to see the boot menu. Select “Linux”. Note: For this, “F12 boot menu” must be enabled in the BIOS settings (Press F2 while booting).

5) In the menu, select “Try ubuntu without installing”, for Live Ubuntu session.

6) Connect to your WiFi. Download and run boot-repair using the following commands:

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

Just follow the prompts, till you get the message that the grub is fixed. It worked for me.

Thanks 🙂

Answered By: umash07

In my case, there is no path likes EFIubuntugrubx64.efi when running bcdedit /enum firmware. It is EFIubuntushimx64.efi. Run the following command in Administrator mode of cmd:

bcdedit /set {bootmgr} path EFIubuntushimx64.efi

It worked for me.
Dual boot Windows 10 (1909) and Ubuntu 16.04.

Answered By: le hien