I have a dualboot system with Ubuntu 20.04 and Windows 10 on one harddrive. Everything worked well for the last 4 weeks until an hour ago:

All of the sudden I got this error when trying to start Windows from GRUB:

error: file '/EFI/Microsoft/Boot/bootmgfw.efi' not found

What can I do about this problem?

What I tried and checked so far:

  • Updated grub
  • Checked the given file: it does exist! And it got a size of 1558328 bytes so it's not empty
  • Followed this answer and tried boot-repair as well as Rescatux (Reinstall Mictrosoft Windows UEFI)

Here is a report of my current boot setup as analyzed by boot-repair.

None of those trys fixed it so far. Has anyone got a solution or at least something to try?


So what I achieved so far is that I'm able to boot into both OS again using UEFI. When pressing DEL on startup I can use the UEFI's boot menu to boot into grub (and into ubuntu from there) or into windows. But when starting into grub and trying to start windows from there I still get the same error message. Here is another boot report as analyzed by boot-repair. As you can see on line 97

Boot0011* (Rescapp) bootmgfw.efi    HD(1,GPT,84e08278-2d18-4a4c-9885-fde204e033e6,0x800,0x32000)/File(\EFI_PRE_RESCATUX_2020-09-01-20-46-59\Microsoft\Boot\bootmgfw.efi)

there is an entry on UEFI to boot into windows. But this entry uses a backup of the EFI to boot into windows. GRUB instead uses a more recent file to try to boot windows as you can see here in the grub.cfg file:

### BEGIN /etc/grub.d/30_os-prober ###
menuentry 'Windows Boot Manager (on /dev/sda1)' --class windows --class os $menuentry_id_option 'osprober-efi-92CE-E05A' {
    insmod part_gpt
    insmod fat
    set root='hd0,gpt1'
    if [ x$feature_platform_search_hint = xy ]; then
      search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt1 --hint-efi=hd0,gpt1 --hint-baremetal=ahci0,gpt1  92CE-E05A
      search --no-floppy --fs-uuid --set=root 92CE-E05A
    chainloader /EFI/Microsoft/Boot/bootmgfw.efi
set timeout_style=menu
if [ "${timeout}" = 0 ]; then
  set timeout=10
### END /etc/grub.d/30_os-prober ###

I though about simply changing line




but on top of the file it says that you shouldn't edit this config file so I dont dare to do so. Could it break anything? And why does only the backed up version works and not the recent one? My whole boot setup looks a little messed to me.

  • 1
    Did Windows do an update & turn fast start up back on? Grub only boots working Windows or Windows that is not hibernated nor needs chkdsk. But it does not look like you have an UEFI Windows boot entry to directly boot it from UEFI. See IV for UEFI entry using efiboomgr. askubuntu.com/questions/486752/… See also man efibootmgr
    – oldfred
    Sep 1, 2020 at 22:09
  • Windows did at least some updates. I turned it off and restarted shutdown and restart into windows two times. After hat I started ubuntu and boot-repair. But the status summary still says: Windows is hibernated, refused to mount. Falling back to read-only mount because the NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting.). Seems like something went wrong there? I followed this instruction [asus.com/us/support/FAQ/1031533/] When I start into windows the logo appears so I does a least look like if it's deactivated
    – Tayfe
    Sep 4, 2020 at 0:06
  • And Rescatux somehow got me an UEFI entry to directly boot into windows from UEFI so at least I'm able to use windows again. But I got no clue how it did it, how I can fix grub to do the same. And for some reason I can't boot from my US stick with Rescatux anymore? It's shown in the list in UEFI [imgur.com/a/9GwYE7P] but when clicking there's just a black screen for like a second and my the laptop returns to the UEFI menu again.
    – Tayfe
    Sep 4, 2020 at 0:17
  • What brand/model system? What video card/chip? Sometimes during install something gets written to flash drive, so it does not work and needs to be recreated. Black screen is usually video issue. askubuntu.com/questions/162075/…
    – oldfred
    Sep 4, 2020 at 3:30
  • I got a laptop "HP Elitebook 840 G3" with Intel 6200U and HD520. But I doesn't feel like a problem related to the graphic card since it's always working. The black screen seems rather to be a booting issue
    – Tayfe
    Sep 4, 2020 at 10:01

9 Answers 9


It is work for me.

  1. Create a bootable windows 10 USB.
  2. Select USB from boot menu.
  3. "Repair your computer" > Troubleshoot > Startup Repair.
  4. Done

It take few seconds. :)

  • This worked for me!!!
    – codetiger
    Mar 3, 2021 at 5:24

I had the same problem as Tayfe(top most post), suddenly when ever i selected windows 10 from the grub boot menu this error popped up "error: file '/EFI/Microsoft/Boot/bootmgfw.efi' not found".

I tried editing the grub.cfg file as mentioned above but it did not help.

The efi file was there when i browsed to the location using file explorer its just that during booting it was not being found.

What i did to fix it was (first from boot menu disabled secure boot)(edited)

1.Created a bootable windows 10 usb

1a.downloaded the windows 10 iso from windows official website.

1b.Used balenaEtcher(this is the only rufus alternative i found for ubuntu) to create a bootable windows 10 media.

  1b1.First format the usb.

  1b2.Then using Gparted(in device tab in Gparted) create a new partition table (type of partition == GPT ).

  1b3.then created a new partition of fat32 type(allocated all the space to this partition so there is only a single partition on the usb)

1bc.Used balena etcher to etch the windows 10 iso file onto this usb(it gave a warning regarding the iso that it might not get recognised ignore it(i did)).

2.Now once u have a bootable windows 10 usb, restart the pc and when u are in the grub boot menu press c to enter the command line.

3.Press ls.

4.It will show all the harddrives on the pc.

5.My usb was (hd0) (yours may appear different but u can find it by first doing the "ls" part without having the usb inserted then again with the usb inserted) or like in the next step

6.to see the detail about a harddisk (eg for the (hd0) do "ls (hd0)" it will show you the details , i knew this is my bootable usb by comparing the size and also the name, eg for (hd1,msdos) run "ls (hd1,msdos)" like this).

7.Now run "set root=(hd0)" your "(hd0)" part may be diff.

8.now run "ls -l /"

9.this will show all the files on the root which is the usb now

10.if there is a "efi" DIR then everything is fine and u can follow along.

11.now just check "ls -l /efi/boot/" has an efi file or not mine showed me a file bootx64.efi when i ran this command.

12.You can also make sure your path "/efi/boot/bootx64.efi" is a correct path by opening the usb in ubuntu first and going to this path from the file explorer to check everything

13.So after the run root=(hd0) command, run this command "chainloader /efi/boot/bootx64.efi"

14.then if the command ran okay, run "boot".

15.this will boot into windows 10 installation, follow this link (https://www.thewindowsclub.com/boot-or-repair-windows-10-using-the-installation-media) from step number 3 or the instructions below

15a When you boot from the USB drive, it will kickstart Windows 10 installation. Do not have a craving to keep hitting next, or you will end up installing Windows. On the first installation screen, look for a link “Repair your computer.” Click on it. It will boot your computer into Advanced Recovery.

15b When at the advanced troubleshooting, select Advanced Options. Select Troubleshoot. Under Advanced options screen, you will see Startup Repair. Click on it and follow the instructions.

16.I followed all this and my error was fixed, hope the same happens for you.

  • Thanks for the detailed steps. It worked.
    – Tanvir
    Feb 17, 2021 at 16:11
  • Thank you, it's my case
    – Jackssn
    Oct 31, 2021 at 17:13

I'm not sure whats the exact way to solve this problem. But I tried a few thing and finally came up with a solution! So at least a small summarize:

At some point I felt like I had completely messed up the UEFI. When booting the laptop mouse and keyboard were flashing once before they turned them self off again just before even GRUB or UEFI could be loaded. And when trying to boot from a USB stick I also got stuck with a blank screen. So I decided to simply reset the UEFI to factory standards. This solved the problems with mouse, keyboard and USB stick!

To solve the actual problem

error: file '/EFI/Microsoft/Boot/bootmgfw.efi' not found

I decided to give it a try and edit /boot/grub/grub.cfg as mentioned in my first post. I changed just this one single line, nothing else! This made it working for me! So now I can boot into Ubuntu and Windows 10 again from GRUB. The only thing I'm actually wondering about is where I got this file at /EFI_PRE_RESCATUX_2020-09-01-20-46-59/Microsoft/Boot/bootmgfw.efi from. Yes it looks a lot like Rescatux is responsible for this but I don't know exactly what I did that rescatux created this backup file.

Good luck if you're facing a similar problem! :)


Seems like each answer has a completely different experience with resolving this issue. Mine was quite more simple: I checked whether I had any space left on the /boot/ device with df -h, and it was completely full. I had several FSCKXXXX.rec inside /boot/efi (which I acessed with root after running sudo su), which were probably some leftover from previous inadvertent disk checks. I removed them all, disk was not full anymore and I could boot Windows again without further issues.


Here's a much simpler alternative. It worked like a charm for me and can probably save thousands of other desperate souls.

  1. Download this file and save it in the Downloads folder.

  2. Save your Home Path in /tmp/home.txt:

    echo "$HOME" > /tmp/home.txt
  3. Export variable HOMEOLD:

    export HOMEOLD=$(cat /tmp/home.txt)
  4. Copy .tar.gz file to EFI directory:

    sudo cp $HOMEOLD/Downloads/WindowsBoot.tar.gz /boot/efi/EFI
  5. Enter the EFI directory:

    cd /boot/efi/EFI
  6. Decompress .tar.gz file:

    sudo tar -xzf WindowsBoot.tar.gz
  7. Delete .tar.gz file:

    sudo rm WindowsBoot.tar.gz
  8. Reboot and voilà!

    sudo reboot

Credit to Vinicius Rolins, a random Brazilian YouTuber who shared this solution in his channel, he also published a tutorial in Portuguese),..

  • Worked for me, thank you so much! Oct 25, 2021 at 18:56

Thanks. I followed your decision, and it works for me too! I'll put all steps here:

  1. Create a LiveCD with Rescatux.
  2. Load the Rescatux system on your PC.
  3. Into the "Boot" section, click the Reinstall windows MBR button (It automatically creates actual boot-file in a path such as EFI_PRE_RESCATUX_2020-09-01-20-46-59/Microsoft/Boot/bootmgfw.efi)
  4. Load your Linux system (Ubuntu or etc) and open the file /boot/grub/grub.cfg
  5. Change the string /EFI/Microsoft/Boot/bootmgfw.efi to /EFI_PRE_RESCATUX_2020-09-01-20-46-59/Microsoft/Boot/bootmgfw.efi
  6. Enjoy!

Well i‘m not sure if this is very helpful but for me plugging in my win11-external drive into my computer „fixed“ the problem lol


For others, who have same problem, but file is really missing.

On my PC installed windows and Ubuntu on the same physical disk, after trouble with power off, I got this problem.

My solution I boot Ubuntu, go to the folder, where was installed windows, and just copied this file, past in the Ubuntu folder, that's it, good luck!


Try Boot repair.

  1. Add Boot-Repair's repository to your software sources.

    sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt update
  2. Install boot repair.

    sudo apt-get install -y boot-repair && (boot-repair &)
  3. Run boot-repair.

  4. Restart machine with sudo reboot

  5. Now you will be able to copy efi folder /boot/EFI/Microsoft/Boot . Copy downloaded or copied from other machines with same conf. bootmgfw.efi to that folder.

Now you may be able to boot.

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.