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Fix UEFI Boot In Windows 10

UEFI (EFI) or Unified Extensible Firmware Interface is an updated version of BIOS. These days, all the famous PC brands are designed with UEFI/EFI instead of BIOS.

This change brings several improvements to the system like advanced security measures, faster boot times, support for disks larger than 2.2 TB, and many more.

But, once UEFI gets damaged or corrupted then it affects the bootloader and makes them broken. Because of the corrupted UEFI or broken bootloader Windows system gets unable to reboot normally.

If you are also experiencing the UEFI bootable issue or failed to boot your Windows 10 computer, then don’t worry as you are not the only one. There are a number of Windows 10 users who are going through the same issue.

Thankfully, there are some solutions that will help you to fix these UEFI boot issues on your computer. If you are one of these users, then this article is for you.

In this article you will be provided with the fixes that will help you to fix UEFI boot in Windows 10 computer with ease. So, go through the fixes one by one to get rid of this issue.

How Can You Fix UEFI Boot Errors in Windows 10?

Fix 1: Use Diskpart to Fix Windows 10 UEFI Boot Error

The most common solution which you should try to fix UEFI Boot in Windows 10 is using diskpart. Diskpart is a command-line disk partitioning utility.

Therefore, if you are having UEFI boot issues on Windows 10, then you can take advantage of DiskPart utility. If you don’t know how to use diskpart, then follow the quick guide given below:

  • Firstly, insert the Windows 10 installation disk or installation USB into your PC /Laptop and boot from the disk or USB.
  • You will see an Install now screen, here click on the Repair your computer or press F8

UEFI Boot errors in Windows 10

  • Click Troubleshoot > Advanced optionsCommand Prompt

UEFI bootloader error

  • After it, type the below command in the Command Prompt and press the Enter key after each command:


list disk

sel disk 0

UEFI issues

  • If you see the message “Disk 0 is now the selected disk” then type the given command and hit the Enter key:

list vol

Diskpart utility

  • After it, diskpart will display the complete list of volumes on your computer. Here, you need to search for the UEFI volume from the list. Go to the list: UEFI partition will be on Volume 2.
  • Enter the below-given command and press Enter key after every command:

sel vol 2

set id=ebd0a0a2-b9e5-4433-87c0-68b6b72699c7

selecting disk volume

  • Now, type the given command to assign a letter to your drive and make sure the letter which you are going to assign is unique and not in use by other drives:

ssign letter=G

assigning disk letter

  • After assigning a drive letter, you will see the message “DiskPart successfully assigned the drive letter or mount point”
  • Now type exit and press Enter
  • Open Command Prompt again and type the below command and press Enter key after each command:

cd /d G:\EFI\Microsoft\Boot\

cd /d G:\Boot\ or cd /d G:\ESD\Windows\EFI\Microsoft\Boot\

Repair UEFI boot

Note: Now, in the previous steps you assigned ‘G’ as the drive letter to UEFI partition. So remember to replace G with your UEFI’s partition letter.

bootrec /fixboot

fix Windows boot

ren BCD BCD.bak
bcdboot C:\Windows /l en-us /s x: /f ALL

Windows 10 UEFI boot issue

Note: Here, c:\ is the system drive where the Windows OS is installed on.

  • After it, you need to run the below-given command:

bootrec /rebuildbcd 

  • Hit Enter to run
  • Lastly, close the Command Prompt and reboot PC.

After, applying all the above-discussed steps carefully you will see that UEFI boot is fixed and Windows 10 can run normally again.

Fix 2: Use Automatic Repair to Resolve UEFI Boot Issues on Windows 10

If using diskpart didn’t get your work done and you are still incapable to boot your Windows 10 computer, then try the Automatic Repair. Automatic Repair is a Windows 10 inbuilt utility that users apply to fix normal Windows errors.

This might help you to fix the UEFI boot issue on the Windows 10 computer and is also a less complex way to deal with this issue.

To apply this solution, follow these steps:

  • At first, insert the Windows 10 installation disk or USB on your PC/laptop.
  • Reboot your computer or laptop and boot from the disk or USB;
  • On the Install now screen, click on the Repair your computer
  • Select Troubleshoot at Choose an option screen

Troubleshoot UEFI boot error

  • Click on the Automatic Repair

Automatic repair

  • Select an account from the list
  • Lastly, wait until the repair process gets finished.

Fix 3: Add the Disk Driver

If you have replaced the RAID with another machine or replaced the original IDE disk or SATA with new NVMe SSD, then this might be the reason for the UEFI bootloader issue on your Windows 10 computer.

Hence, to fix this UEFI boot issue, you can follow the given Windows command line:

  • Firstly, open Command Prompt as administrator. For this, follow these steps:
    • Type cmd in Windows Search box
    • Right-click on the Command Prompt and select Run as administrator

UEFI bootloader crashed

  • In the Command Prompt, type the given command and press Enter key:

Dism /Image:H: /Add-Driver /Driver:”y:\z.inf”

Please Note: In this command X shows the disk character of restored Windows boot partition, whereas the command under the double quotes shows the location of driver and INF file.

  • After executing the command, type exit and press the Enter key to close the Command Prompt.

Fix  4: Change the BIOS Settings

UEFI bootloader issue may also occur when you are not choosing the appropriate boot mode. You are supposed to choose the boot mode according to the disk type on your computer.

If you are trying to start the MBR system disk, then you need to select the Legacy support rather than the UEFI in the boot mode. Similarly, to start the GPT system disk, choose the UEFI boot mode.

Easy Solution to Boost Your PC’s Performance

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This tool is also capable to fix various PC related issues and also keeps PC safe from viruses and malware. Furthermore, it also fixes DLL, BSOD, game errors, registry issues, repairs damaged or corrupted system files, and more.

Hence, give a try to this tool if you are facing any of such PC related issues as it is easy to use and consumes less time than dealing issues manually.

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That’s all!! Here you have the best working solutions to fix the UEFI boot in Windows 10 computer.

As these solutions are already tested by the affected users, hence it might help in your case too.

I hope that Windows 10 UEFI boot error is resolved on your system and your Windows 10 computer became normal after applying the above-given fixes.

However, if you still have any queries or suggestions, then you can share it with us on our social media handles – Facebookor Twitter.

Jack Adision

Always up to help others for their PC related issues, Jack loves to write on subjects such as Windows 10, Xbox, and numerous technical things. In his free time, he loves to play with his dog “Bruno” and hang out with his friends.

Categories Windows ErrorsTags Fix UEFI Boot in Windows 10, get rid of UEFI Boot in Windows 10, UEFI boot error on Windows 10, uefi boot windows 10, UEFI Bootloader IssueSours: https://www.pcerror-fix.com/complete-tutorial-fix-uefi-boot-windows-10-8-1-8-7

How to fix UEFI boot problems in Windows 10

Andrew is not just trying to bring you closer to Windows, but he's truly interested in this platform. He just happens to be passionate about sharing that knowledge with our readers and that’s what... Read more

  • UEFI, or if you prefer Unified Extensible Firmware Interface, is a protocol that is replacing the popular BIOS with new software.
  • A broken UEFI means that you have a broken bootloader which also means that you won’t be able to reboot or power on your Windows 10 device.
  • For any other booting problems, head on to your Troubleshooting Boot errors on Windows PC section and you will find a solution fast.
  • Don't get mad if you get any Windows 10 errors. Get even and visit our Windows 10 errors hub for some quick and correct solutions.
how to fix UEFI boot problems in Windows 10


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Windows 8, 8.1 and Windows 10 boot problems might be quite annoying since the troubleshooting process is usually complex. Because of that most of the users are choosing to reinstall the Windows system instead of fixing it.

If you want to try to fix your Windows 8, Windows 10 UEFI boot problems,  follow the guidelines below.

UEFI, or if you prefer Unified Extensible Firmware Interface is a protocol that is replacing the popular BIOS with new software.

UEFI is adding some important advantages such as improved security measures, faster startup times, support for disks larger than 2.2 TB, and lots more.

Now a broken UEFI means that you have a broken bootloader which also means that you won’t be able to reboot or power on your Windows 8 / Windows 8.1/ Windows 10 device.

You can also have a look at these related useful tips: learn how to fix chkdsk in Windows 8, 10, or how to view BSOD details in Windows.

Therefore, fixing UEFI boot problems is essential especially if you want to use your device without having to reinstall the Windows 8, 8.1, 10 OS system.

So, if I have convinced you to follow this tutorial, don’t hesitate and try the troubleshooting solution from below.

How can I fix Windows UEFI boot problems?

  1. Use diskpart and recreate Boot Configuration Data
  2. Repair your computer

1.  Use diskpart and recreate Boot Configuration Data

  1. Insert the Windows installer disk on your computer.
  2. Reboot and press any key in order to boot from Windows DVD.
  3. Wait while the Installer sequence is loading all the files.
  4. Then, click on Next and Repair your computer.repair computer
  5. Furthermore, go to Advanced options and pick Command Prompt.cmd from wind 8 installer
  6. Good, now a cmd window will be displayed on your device.
  7. On the cmd window type diskpart.
  8. Find out on which disk you have installed Windows by entering list disk.
  9. Usually, the Windows system is installed on disk 0 – if not change the following command accordingly to the number of your disk.
  10. In cmd type sel disk 0.
  11. You have selected your disk; now type list vol in order to show all the partitions.diskpart
  12. The UEFI partition should be a FAT32 file system – let’s say that is volume number 3.
  13. Select your partition by typing the sel vol 3 command and assign a new letter to your volume by using the command assign letter=b (you can set any letter you want, this is only an example).assign letter
  14. Enter exit and press enter.
  15. Up next you will need to type cd /d b:EFIMicrosoftBoot followed by bootrec /fixboot in order to repair boot record.
  16. Then you have to recreate the Boot Configuration Data (BCD), so in cmd type ren BCD BCD.old followed by bcdboot c:Windows /l en-us /s b: /f ALL.
  17. Perfect; all you have to do is to reject the Windows 8/ Windows 8.1 disk and to reboot your device as you are done.

You might be interested in our guide on how to Create a Windows 10 Bootable UEFI USB Drive

2. Repair your computer

Another way to fix UEFI boot issues in Windows 10 is to simply repair your computer.

This method is somehow similar to the first steps of the solution listed above, yet it’s less complex, so if you’re an average Windows user, you may want to use this solution first. Here are the steps to follow:

  1. Insert the Windows 10 install disk/ install USB to your computer
  2. Restart the PC > select boot from the disk/USB
  3. On the Install now screen > select Repair your computer
  4. Go to Troubleshoot > click on Automatic Repair
  5. Choose the problematic account from the list > confirm your choice and wait for the repair process to complete.

So, that was how you can easily fix Windows 8, 10 UEFI Boot Problems.

Do feedback us by using the comments field from below and share your other Windows issues with us in order to get technical assistance.

If you’ve got additional tips and suggestions on how to fix UEFI boot problems, you can list them in the comments below.

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3 Easy Way to Repair Windows 10 UEFI/EFI Bootloader

UEFI or Unified Extensible Firmware Interface is a feature of PC which works as a software interface between the operating system and the platform firmware. But this interface sometime creates annoying booting problems as problem of bootloader. This article will tell 3 ways to repair Windows 10 bootloader with ease.

1. Fix Windows 10 Bootloader with Automatic Repair

The first method to repair Windows 10 UEFI bootloader is through automatic repair. This is an in-built feature of Windows 10 disc which can help to repair EFI bootloader windows 10. To use this method, Windows setup CD/DVD or a USB is required. Follow the below mentioned instructions to fix Windows 10 bootloader through automatic repair method.

• First insert the Windows 10 installation disc or USB to the PC.

• Then restart the PC and boot it from the Windows 10 installation disc or the USB.

• When the "Install Now" screen appears on the monitor click on the "Repair your computer" option.

windows setup

• Then "Choose an option" screen will pop up; there select "Troubleshoot" option from the listings.

windows 8 recovery options screen troubleshoot

• Then click on the "Automatic Repair" option.

• At the "Automatic Repair" screen the PC will ask for an account from the given list to for continuing the process.

• After selecting the desired account wait for a while until the process is completed. And hence the bootloader will be fixed.

2. Repair Windows 10 Bootloader with diskpart

Using the diskpart method is proved one of the most effective ways to deal with bootloader problems. If automatic repair doesn't work then this one is the next thing to try. Diskpart can be also used on the first go as it is assured to be more efficient than automatic repair method.

Generally bootloader problems arise due to the fact that sometimes the UEFI partition of the PC won't possesses an assigned drive letter. This is the most basic cause of bootloader failure. The usual solution is to assign a letter to the unassigned drives via using the diskpart utility which is present on the Windows 10 recovery disc or USB flash drive. This method also asks for the windows setup CD/DVD or USB. To fix the bootloader of Windows 10 operating system through diskpart follow these steps as mentioned below.

• Put the Windows 10 setup CD/DVD or USB in the PC. Restart the PC and boot it from the Windows 10 setup CD/DVD or USB.

• When "Install now" screen pops up select "Repair your computer" option or simply press "R" from the keyboard.

• Then select the "Troubleshoot" alternative from the listings.

windows 10 advanced startup troubleshoot

• Then click on the "Advance options" choice.

advanced options

• From the listings choose "Command Prompt" to launch it. When the command prompt window pops up then you need to type in the following commands and hit enter each time.



sel disk 0

• After getting the confirmation message "Disk 0 is now the selected disk" , type in "list vol".

• Again press "Enter" from the keyboard. Now the diskpart will display all the list of volumes present on the PC.

repair Windows 10 bootloader

• Locate the required UEFI one from the given list of volumes. The right one will have "BOOT" shown on its Label column and "System" on the Info column. The Fs column if shown then it will show FAT32 format.

• Let us suppose that the UEFI partition is present on volume 2, type in "sel vol 2" in the command prompt and press "Enter" from the keyboard.

• Then use the following command to assign a letter to the drive "assign letter =G:" do not use the letter which is already in use for other drives such as C:\ or D:\

• Now again press "Enter" from the keyboard and then stop for the confirmation message to come up on the screen as :

"Diskpart successfully assigned the drive letter or mount point." Now type in the following commands and hit enter each time.


cd /d G:\EFI\Microsoft\Boot\

cd /d G:\Boot\ or cd /d G:\ESD\Windows\EFI\Microsoft\Boot\

Note: The letter "G" in this command may change depending on what name is used by the user to assign to the drive.

bootrec /fixboot

ren BCD BCD.bak

bcdboot C:\Windows /l en-us /s x: /f ALL Note: c:\ is the drive where Windows 10/8.1/8 is installed on.

w8 uefi fix

• The C:\ used in the command is to specify the drive where the Windows 10 is installed.

• After typing the command press "Enter" from the keyboard.

• As an alternative to the big command mentioned in the previous step use can use the below mentioned command also to reconstruct the BCD data:

"bootrec /recbuildbcd"

• Press "Enter" from the keyboard.

• After the BCD data is built type "exit" in the command prompt to close it.

• Then restart the PC. Windows 10 should now boot normally again.

3. Repair Windows 10 UEFI/EFI Bootloader with Windows Boot Genius

The 3rd way to fix the bootloader is via using windows rescue in Windows Boot Genius.Windows Boot Genius is the software which can help the user in many booting problems. It can easily resolve the bootloader problem. User just needs to follow the below mentioned steps.

Buy Now($19.95)

• Download Windows Boot Genius and launch it.

• Put an empty CD or USB into a workable computer. Click on "Burn" to create a bootable CD or USB.

fix windows 10 bootloader

• Insert the bootable CD or USB to the problematic PC and press F12 key from the keyboard to access the Boot Menu. Select the CD or USB as the first boot device. The key may change according to the mainboard of the PC.

• After successful entry into WinPE environment, user will see the icon of Windows Boot Genius. Launch Windows Boot Genius to get into Windows Rescue mode to repair Windows 10 UEFI/EFI bootloader under the "Crash before loading" instruction.

repair windows 10 bootloader

That's all about how to repair Windows 10 UEFI/EFI Bootloader. If you don't have much professional skills on Windows system, Windows Boot Genius may be a better choice for you.

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How to Enable UEFI Boot in ASUS Mother Board / CSM -Compatibility Support Module


The Extensible Firmware Interface (EFI) or its version 2.x variant, Unified EFI (UEFI) is a firmware type that is widespread on recent computers, especially those more recent than 2010. It is intended to replace the traditional BIOS firmware that is prevalent on earlier machines. This page provides information about installing and booting Ubuntu using UEFI, as well as about switching between UEFI mode and legacy BIOS mode using Ubuntu. Warning /!\ Most modern computers support both UEFI mode and BIOS mode. Which boot mode you should use depends on several factors:

  • Boot mode matching -- If you're dual-booting with another OS, the two OSes' boot modes should match. Most computers that ship with Windows 8 and later use UEFI to boot that OS, so this configuration dictates use of UEFI mode when installing and booting Ubuntu.

  • Hardware support -- Some hardware devices work better in one mode or the other. (Usually BIOS mode is better supported.) This type of problem is becoming less common.

  • Boot loader problems -- Sometimes a boot loader for one mode works better than a boot loader for another mode. BIOS-mode boot loaders are better tested and are therefore less likely to pose problems.

Note that these factors can conflict with one another. For instance, if you're dual-booting with a pre-installed Windows 8 but have problems getting a UEFI version of GRUB to work, you'll be in a bind. As a general rule, though, UEFI mode works better in dual-boot setups with pre-installed versions of Windows 8. If you're installing Ubuntu as the sole OS on a computer, either mode is likely to work, although BIOS mode is less likely to cause problems.

The following sections describe how to install Ubuntu in UEFI mode, either because you're single-booting and want to try this boot mode or because you're dual-booting with another OS that's already installed in this mode.

Case when Ubuntu must be installed in UEFI mode

Having a PC with UEFI firmware does not mean that you need to install Ubuntu in UEFI mode. What is important is below:

  • if the other systems (Windows Vista/7/8, GNU/Linux...) of your computer are installed in UEFI mode, then you must install Ubuntu in UEFI mode too.
  • if the other systems (Windows, GNU/Linux...) of your computer are installed in Legacy (not-UEFI) mode, then you must install Ubuntu in Legacy mode too. Eg if your computer is old (<2010), is 32bits, or was sold with a pre-installed Windows XP.

  • if Ubuntu is the only operating system on your computer, then it does not matter whether you install Ubuntu in UEFI mode or not.

General principles

To install Ubuntu in UEFI mode:

  • Use a 64bit disk of Ubuntu. (Ubuntu32bit cannot be easily installed in UEFI mode. This is a problem if 32-bit UEFI is the only way your computer can boot, e.g. if you have a modern Intel Atom based laptop. In this case, you will need a complicated work-around.)

  • In your firmware, disable QuickBoot/FastBoot and Intel Smart Response Technology (SRT). If you have Windows 8, also disable Fast Startup.

  • You might want to use an EFI-only image to avoid troubles with mistakenly booting the image and installing Ubuntu in BIOS mode.

  • Use a supported version of Ubuntu. Support for UEFI appeared in 11.10, but has become more reliable in next versions. Support for UEFI SecureBoot appeared in 12.10 and 12.04.2.

  • Set up your firmware (BIOS) to boot the disk in UEFI mode (see the "Identifying if the computer boots the HDD in UEFI mode" paragraph below)

  • Then:
    • nothing special is required if you use the automatic installer of Ubuntu ("Install Ubuntu alongside others" or "Erase the disk and install Ubuntu"). Important: if you have a pre-installed Windows and you want to keep it, do not choose "Erase the disk and install Ubuntu".
    • if you use the manual partitioning ("Something else"), the difference is that you will have to set the /boot/efi mount point to the UEFI partition. And if there was not any UEFI partition on your HDD, you first will have to create it (see the "Creating an UEFI partition" paragraph below).


Identifying if the computer boots the HDD in UEFI mode

This is possible only if you have already installed Ubuntu on the HDD, or by looking at the BIOS setup (see paragraph below).

From an Ubuntu installed on the HDD (neither liveCD nor liveUSB), open a terminal (Ctrl+Alt+T), then type the following command:

Remark: if the result is "Legacy boot on HDD", then either the BIOS is not UEFI type, or the BIOS is not set up to boot the HDD in UEFI mode.

Identifying if the computer boots the Ubuntu DVD in UEFI mode

Warning: even if your PC boots the DVD in UEFI mode, it might boot the HDD in Legacy mode (and the contrary).

When booting on a 64-bit Ubuntu disk:

- If the BIOS is set up to boot the CD in UEFI mode, then you will see the screen below:


- If the BIOS is NOT set up to boot the CD in UEFI mode, or if the disk is not 64-bit, then you will see the screen below:


Set up the firmware in UEFI or BIOS/CSM/Legacy mode

Some recent computers (>2011) allow you to set up the computer to boot either in UEFI mode or in BIOS/CSM/Legacy (not-EFI) mode. The way to adjust this setting depends on the computers, but generally this setting is located in the "Boot order" tab of the BIOS (to access the BIOS screens, it is generally necessary to press a key during the PC startup). It can also often be set on a per-boot basis by hitting a function key (F8 and F10 are common choices) soon after you power on the computer.

Note: Some UEFIs (e.g. American Megatrends' "Aptio", found on the Asus vivobook series) call Legacy mode "Compatibility Support Module" or simply "CSM".

Remark: Some UEFIs enable one to set up the boot mode for the optical drive separately from the boot mode for the HDD.

For example, below:

  • the "UEFI Hitachi" line allows to boot the HDD in UEFI mode,
  • the "P1: Hitachi" line allows to boot the HDD in Legacy (not-UEFI) mode,
  • the "P3: DVD" line allows to boot the Ubuntu CD in Legacy mode
  • the "UEFI: USB" line allows to boot the Ubuntu liveUSB in UEFI mode.


Here is a 2nd example of UEFI boot mode setting, where the "Boot Mode" parameter enables one to choose the boot mode ("UEFI" or "Legacy") for all media (hard disk, CD, USB...) at the same time.


Some other UEFIs propose an "UEFI/Legacy Boot:" option with the following choices: [Legacy only], [UEFI only] and [Both]. This last one boots in UEFI mode when possible, then in Legacy mode if no UEFI files are detected.

Creating an EFI System Partition

If you are manually partitioning your disk in the Ubuntu installer, you need to make sure you have an EFI System Partition (ESP) set up. This partition holds EFI-mode boot loaders and related files.

  • If your disk already contains an ESP (eg if your computer had Windows 8 preinstalled), it can be used for Ubuntu too. Do not format it. It is strongly recommended to have only 1 ESP per disk.

  • An ESP can be created via a recent version of GParted (the Gparted version included in the 12.04 disk is OK), and must have the following attributes:

    • Mount point: /boot/efi (remark: no need to set this mount point when using the manual partitioning, the Ubuntu installer will detect it automatically)

    • Size: minimum 100Mib. 200MiB recommended.

    • Type: FAT32

    • Other: needs a "boot" flag.

Performing the Installation

Once you've taken care of the preliminaries, you can install Ubuntu normally. Aside from the ESP, Ubuntu installed in UEFI mode has no special partition requirements, and you need not adjust other installation options. Note that in a UEFI-mode installation, Ubuntu will not ask you where to install the boot loader. If it does, or if it complains about the lack of a BIOS Boot Partition, you've probably accidentally booted in BIOS/CSM/legacy mode.

An Ubuntu installed in UEFI mode can be detected the following way:

  • its /etc/fstab file contains an UEFI partition (mount point: /boot/efi)
  • it uses the grub-efi bootloader (not grub-pc)
  • from the installed Ubuntu, open a terminal (Ctrl+Alt+T) then type the following command:

    [ -d /sys/firmware/efi ] && echo "Installed in UEFI mode" || echo "Installed in Legacy mode"

If you aren't multi-booting with another OS and you don't care about your boot mode, you can forego some of the picky details of the preceding procedure and install Ubuntu in whatever boot mode your computer happens to pick. This procedure is not recommended for multi-boot installations alongside existing UEFI-based OSes, because it can result in a combination of one OS installed in UEFI mode and the other in BIOS mode. Such setups will require post-installation repair or other awkward steps to manage switching OSes.

You should be able to get Ubuntu installed quickly using the following steps:

  • Create a LiveDVD or LiveUSB of Ubuntu (>=12.04.2) 64bit.

  • In your firmware, disable QuickBoot/FastBoot and Intel Smart Response Technology (SRT).

  • Boot your PC using the LiveDVD or LiveUSB and choose "Try Ubuntu". If you get a Secure boot or signature error, you may wish to disable SecureBoot as described here, then retry to boot the disk.

  • Install Ubuntu from the Live CD/DVD or Live USB in the usual manner, then reboot the PC.
  • If the PC does not load Ubuntu, boot your PC using the Live CD/DVD or Live USB and choose "Try Ubuntu" once again. When the live session has loaded, run Boot-Repair (see link for details). When Boot-Repair loads, click on the "Recommended repair" button, and write on a paper the URL (paste.ubuntu.com/XXXXXX/) that will appear. Then reboot the computer. Do not run Boot-Repair unless you have problems booting the computer; the expression "if it ain't broke, don't fix it" applies to this tool.

  • This should fix most boot problems. If this does not fix your boot problems, please create a new thread in this forum, describing your problem and indicating the URL you wrote in the previous step.

Converting Ubuntu into UEFI mode

Note: Do not follow this procedure if your computer is already booting correctly. Use this procedure only if you believe you've accidentally installed Ubuntu in BIOS/CSM/legacy mode and you want it to boot in UEFI/UEFI mode.

  • Start Boot-Repair, click on "Advanced options", go to the "GRUB location" tab.

  • If you do not see a "Separate /boot/efi partition" line, this means that your PC does not have any UEFI partition. In this case, exit Boot-Repair, then create an UEFI partition (see the "Creating an UEFI partition" paragraph above).
  • If you see a "Separate /boot/efi partition" line, tick it then click the "Apply" button.
  • Set up your BIOS so that it boots the HDD in UEFI mode (see the ""Set up the BIOS in UEFI or Legacy mode" paragraph above).


Converting Ubuntu into Legacy mode

Note: Use this procedure only to convert an UEFI-mode Linux installation to boot in BIOS/CSM/legacy mode. Such a conversion may be necessary if some hardware doesn't work correctly under UEFI mode. (Video cards are a common source of problems.) Converting to boot in BIOS/CSM/legacy mode while Windows boots in UEFI mode can make the boot process more awkward -- you'll need to use the computer's built-in boot manager to switch between OSes, and some computer's have such poor boot managers that this may be impossible.

  • If Ubuntu is installed on a GPT disk (you can check it via the 'sudo parted -l' command), use Gparted to create a BIOS-Boot partition (1MB, unformatted filesystem, bios_grub flag) at the start of its disk.

  • Start Boot-Repair, click on "Advanced options", go to the "GRUB location" tab.

  • Untick the "Separate /boot/efi partition" option
  • Click the "Apply" button.
  • Set up your BIOS so that it boots the HDD in Legacy mode (see the ""Set up the BIOS in UEFI or Legacy mode" paragraph above).

"Secure Boot" is a new UEFI feature that appeared in 2012, with Windows8 preinstalled computers. All current Ubuntu 64bit (not 32bit) versions now support this feature, but as PCs implementing support for it have only become widespread at the end of 2012 it is not yet widely tested, so it's possible that you may encounter problems booting Ubuntu under Secure Boot. If you do, please file a bug report against the shim package in Ubuntu, preferably using the command once you've installed with Secure Boot disabled.

Disabling SecureBoot in the BIOS

Here is an example of BIOS showing that "Secure Boot" is enabled:


To disable or enable Secure Boot, find a similar option in your BIOS, and use the keyboard to switch it to Enabled/Disabled.

Remark: if your PC has Windows8, you may need to follow the procedure below to access your BIOS.

Accessing the UEFI settings from Windows8

Go to the PowerOff options, and while holding the key, click on .


When the menu below appears, select , then .


The PC will reboot and you will be able to enter the BIOS (if not press the necessary key).

- UEFIBooting (older documentation, maybe useful for Mac)

- EasyBCD cannot be used in UEFI mode: thread on EasyBCD forum. But it can be used from version 2.2.

- Installing Ubuntu on a Pre-Installed UEFI Supported Windows 8 System: Step by Step guide to install Ubuntu on an UEFI/Secure Boot enabled computer that comes pre-installed with Windows 8


Sours: https://help.ubuntu.com/community/UEFI

Repair uefi boot

Windows 11/10 Boot Repair: Fix UEFI Boot Issue on Windows 11/10/8/7

How to do Windows 11/10 boot repair? What are the most useful ways? Read this tutorial and see how to troubleshoot.

Workable SolutionsStep-by-step Troubleshooting
Fix 1. Use Startup RepairYou can fix most Windows 11/10 UEFI boot problems using the Startup Repair tool. Boot Up Windows...Full steps
Fix 2. Use Command PromptIf you are unable to perform a startup repair, then you can try using Windows 11/10 installation...Full steps
Fix 3. Change BIOS SettingsWindows 8, 8.1, 10 and 11 were designed to install on the UEFI BIOS using the EFI bootloader and GPT...Full steps
Fix4. Add Disk DriverManually installing and adding the driver to the restored Windows image can repair UEFI boot...Full steps
Fix 5. Change the SATA ModeYou can change different SATA modes in different cases for Windows 11/10 boot repair...Full steps

Sometimes, Windows 11/10 fails to boot because there is a problem with the master boot record. In these cases, the master boot record needs to be repaired to restart and run. When you want to do Windows 11/10 startup repair, you can use the Windows 11/10 recovery environment includes an automatic option to accomplish this task. If this does not work, you can do it manually with Diskpart command prompt and other effective solutions. In this article, you'll find step-by-step methods to guide you to fix computer UEFI boot errors in Windows 11/10/8/7. Read on to find out how.  Before you start, you can clone your boot drive to another drive with EaseUS Partition Master. Then, follow these steps to fix Windows 11/10 boot repair.

- EaseUS Partition Master -

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You may also read: UEFI vs. BIOS: What's the Difference and How to Check

Method 1. Use Startup Repair for Windows 11/10 Boot Repair

Windows Automatic Repair is a built-in tool for users to apply and try to fix some normal errors on Windows PC. And you may also try this method to repair Windows 11, 10, 8 or 7 UEFI/EFI boot error:

1. Boot Up Windows from Installation Media

Step 1. Insert Windows 11/10/8/7 installation disk or USB to your PC.

Step 2. Restart PC and boot from the disk or USB.

2. Enable Automatic Repair Option

Step 1. Click "Repair your computer" at the Install now screen.

Enable Automatic repair option to fix UEFI error.

Step 2. Click "Troubleshoot" at choosing an option screen > click "Automatic repair".

Use Automatic Repair option to fix UEFI boot error.

Step 3. Choose an account from the list to continue at the Automatic Repair screen and wait for the process to finish.

When the process completes, you can restart your PC, and then you should be able to use your computer without any problems again.

Method 2. Use Diskpart to Fix UEFI Boot Error in Windows 11/10

If you are a Windows 11/10 or 8 user and you prefer free methods to fix UEFI boot error, you may follow below two solutions to solve this issue now:

1. Enter Command Prompt from Advanced Options

Step 1. Insert Windows 11/10/8/7 installation disk or installation USB into PC > boot from the disk or USB.

Step 2. Click "Repair your computer" or hit F8 at the install now screen.

Step 3. Click "Troubleshoot" > "Advanced options" > "Command Prompt".

2. Run Diskpart to Set Partition ID and Assign a Drive Letter

Step 1. Type below command and hit Enter each time:

  • diskpart
  • list disk
  • sel disk 0

Run Disk Part to start fixing UEFI error.

Step 2. When the message "Disk 0 is now the selected disk" shows up, type list vol and hit Enter.

Select disk and volume to set volume ID.

Diskpart will now show the full list of volumes on your PC, find UEFI volume from the list: UEFI partition will be on Volume 2.

Step 3. Type below command and hit Enter each time: 

  • sel vol 2
  • set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b 
  • Or SET ID=ebd0a0a2-b9e5-4433-87c0-68b6b72699c7

Set volume ID to fix volume id.

Step 4. Assign the drive letter by typing below command and click Enter:

  • assign letter=G: (Note: G shall be a unique drive letter which cannot be already used.)

Change drive letter of your selected partition.

3. Repair the Boot Record

  1. Step 1. Open Command Prompt as an administrator, enter below command:
  • cd /d G:\EFI\Microsoft\Boot\ (Note: G is the drive letter you signed to UEFI partition and remember to replace G with UEFI's partition letter)

Repair boot record on UEFI disk.

  • Enter exit when the process completes.
  1. Step 2. To repair the Boot Record, open CMD and enter below command line:

Fix boot record command.

  • Enter exit when the repair process completes.

4. Rebuild the BCD Store

Step 1. Type each command line and hit Enter each time:

  • ren BCD BCD.old
  • bcdboot C:\Windows /1 en-us /s G: /f ALL (Note: c:\ is the drive where Windows 11/10/8.1/8 is installed on.)

Rebuild BDC store on UEFI.

Step 2. Type exit in Command Prompt when the process completes and then restart your PC.

Now UEFI boot is fixed, and Windows 11/10/8/7 can be boot up on your PC again.

Method 3. Change BIOS Settings 

You need to select the boot mode according to the type of disk on your system. If you want to start an MBR system disk, you can select Legacy support instead of UEFI in boot mode. To start a GPT system disk, you need to select UEFI.

How to access BIOS: Common keys to enter the BIOS are F1, F2, F10, Delete, Esc, as well as key combinations like Ctrl + Alt + Esc or Ctrl + Alt + Delete, which are more common on older machines. You can enter the BIOS interface by holding down any of these keys while booting up on your computer.

Method 4. Add Disk Driver to Repair Windows 11/10 Boot

When you replace the RAID with a different machine or replace the original SATA or IDE disk with a newer NVMe SSD, you may encounter problems starting up. You can use the following Windows command line to add the driver to the restored Windows image manually.

Dism /Image:X: /Add-Driver /Driver:"y:\z.inf"

Note: X: is the disk character of the restored Windows boot partition, and in double-quotes is the location of the driver. Inf file.

Method 5. Change the SATA Mode for Windows 11/10 Startup Repair

After the older XP system restores, a blue screen or cycle start may occur, you can change to IDE mode to try to start.

If you run into boot problems after upgrading from an older HDD to a newer SSD, check to see if the BIOS is set to boot for AHCI. If you set it up for RAID mode, make sure the correct RAID driver is added to the cloned system.

To Sum Up

Windows 11/10 boot repair is a rather complicated problem. There are different solutions for different causes and problems. The above approaches only apply to common UEFI boot issues. If none of them can repair UEFI boot error in Windows 10, you can contact our technical support team to get specialized services for system boot issues.

Do You Need Specialized Data Recovery Services?

You may need further help for tough data loss situations like reformatting drive, RAW disk, partition loss, repartition failures and system boot error. Consult with EaseUS Data Recovery Experts for cost-efficient one-on-one manual recovery service. They could offer the following services after FREE diagnosis:
1. Unformat the drive
2. Repair the RAID, RAW disk or operating system
3. Recover lost partition (the one that cannot be recovered by software)

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If you don't want to risk losing or overwriting your important data during the fixes for Windows 11/10 boot repair, you can recover data from a PC/laptop hard drive that won't boot with EaseUS Data Recovery Wizard, a renowned data recovery tool on the market.

To configure and optimize disk performance, you can also turn to EaseUS Partition Master for help.

Windows 11/10 Boot Repair FAQs

The following four questions are highly relevant to UEFI boot repair. Check the answers to get you through.

1. How do you repair Windows 11/10 if it does not boot?

For Windows 11/10 UEFI boot repair, you can perform an automatic startup repair or using command prompt to complete. The step-by-step instructions are given each part, check the guides carefully.

2. How do I repair Windows 11/10?

To repair Windows 11/10 boot, you can use the Startup Repair tool. To access Windows 11/10 recovery environment, turn your computer on and off three times. While booting, ensure you turn off the computer when you see the Windows logo. After the third time, Windows 10 will boot into diagnostics mode. Click "Advanced options" when the recovery screen appears. Then, choose "Startup Repair" and follow the on-screen institutions to do it.

3. How can I repair the Windows 11/10 UEFI bootloader?

To fix Windows 11/10 UEFI boot problem:

  • Insert the Media (DVD/USB) in your PC and restart
  • Boot from the media
  • Select Repair Your Computer
  • Select "Troubleshoot" > "Advanced Options"
  • Choose Command Prompt from the menu and use the dispart command lines: Type and run the command: diskpart. Type and run the command: sel disk 0. Type and run the command: list vol

4. How do I fix a boot startup problem?

There are many effective solutions to fix Windows 11/10 startup issue and repair your EFI Bootloader. You can:

  • Use the Startup Repair tool
  • Use Diskpart in Command Prompt
  • Fix BCD errors
  • Add startup item
  • Change BIOS settings
  • Add disk driver
  • Change SATA mode
  • Fix MBR
  • Restore and repair system partitions
  • more fixes...
Sours: https://www.easeus.com/partition-manager-software/fix-uefi-boot-in-windows-10-8-7.html
How to Enable UEFI Boot in ASUS Mother Board / CSM -Compatibility Support Module

Fix UEFI Boot: Fix for Windows 7, 8, 8.1, 10

This article explains step-by-step solutions that you can use to fix your computer’s UEFI boot for these Windows versions: Windows 7, Windows 8, Windows 8.1andWindows 10.

This how-to article is applicable for PCs with UEFI/EFI that have either Windows 7, Windows 8, Windows 8.1 or Windows 10 installed.


UEFI (EFI) is the updated version of BIOS, which is commonly found on older models of computers. Major PC manufacturers – Dell, HP, Acer, Asus and so on – no longer ship PCs with BIOS, but with UEFI/EFI instead.

Most computers with UEFI/EFI can provide legacy support for BIOS. In this kind of example, if you enable legacy support, you could install Windows 7, Windows Vista or Windows XP on a computer that has UEFI/EFI and not BIOS.

ThinkPad UEFI-Legacy Boot Priority

ThinkPad UEFI-Legacy Boot Priority

PCs with Windows 8 and Windows 8.1 usually have UEFI/EFI installed and not BIOS, but PCs with Windows 7 will use the UEFI/EFI set with Legacy mode active.

Fix UEFI Boot with Easy Recovery Essentials

Easy Recovery Essentials is our EFI and UEFI repair CD/DVD/USB for Windows that can be used to fix your computer.

Easy Recovery Essentials can correct errors in the UEFI/EFI firmware configuration.

Easy Recovery Essentials can fix many errors such as this automatically using its built-in Automated Repair option. EasyRE is currently available for Windows XP, Vista, 7 and 8 and can be downloaded and created on any PC.

  1. Download Easy Recovery Essentials. Make sure to note your Windows version (XP, Vista, 7 or 8) before you download EasyRE. This guide can help you identify what version of Windows you have installed.
  2. Burn the image. Follow these instructions on how to burn the bootable ISO image very carefully, as making a bootable CD can be tricky! Alternatively, these instructions explain how to create a bootable EasyRE recovery USB stick/drive.
  3. Boot up your PC from the Easy Recovery Essentials CD or USB you created.
  4. Once EasyRE is running, choose the “Automated Repair” option and click .
    EasyRE Home

    Choose “Automated Repair” in Easy Recovery Essentials

  5. After EasyRE scans your computer’s drives, identify and select the drive letter for your Windows installation from the list, and then click on the button to begin.
    EasyRE displays a list of found Windows operating systems

    Choose the drive associated with the Windows installation you’re trying to repair.

  6. Easy Recovery Essentials will start analyzing the selected drive for problems. EasyRE will test for and attempt to automatically correct errors with the disk, partition, bootsector, filesystem, bootloader, and registry. No intervention is required, as EasyRE’s repair is fully automated:
    EasyRE: Automated Repair

    Easy Recovery Essentials searches for errors and makes corrections to the selected Windows installation.

  7. Once the process is complete, EasyRE will report its findings. Click on the button to reboot your PC and test the changes.
  8. The “any UEFI boot error” error should now be fixed as your PC begins to load:
    EasyRE: Automated Repair

    Windows, booting up successfully.

You can download Easy Recovery Essentials from here.

Fix UEFI Boot in Windows 7

The step-by-step instructions for fixing the UEFI/EFI boot on a Windows 7 system are very similar to those of Windows 8/8.1:

Windows 7 can’t be installed if your computer’s UEFI/EFI mode is set as active and not in Legacy mode. Legacy mode allows your computer to boot Windows 7.

If your computer model is new and has UEFI/EFI installed, but you have Windows 7 installed, it’s most likely that you’re running UEFI/EFI as Legacy.

Follow the instructions from prerequisites below before you start.


Before you start using the bootrec or the diskpart command to fix the bootloader of your Windows 7 system, first you must determine that UEFI/EFI loads with the Legacy mode active.

Follow these steps:

  1. Restart your computer
  2. Press the necessary key to open UEFI/EFI. The key depends on your PC manufacturer and PC model.Most common keys are: , , , . is also an option.
  3. Once inside the UEFI/EFI setup menu, search for Secure Boot.This is usually found at any of the following tabs: Boot, Authentication or Security.
  4. Make sure Secure Boot is either Disabled or Off
  5. Save these settings and exit the UEFI/EFI setup menu
Secure Boot [Enabled] on a Dell computer

Secure Boot [Enabled] on a Dell computer

Secure Boot [Enabled] on a HP computer

Secure Boot [Enabled] on a HP computer

Fix #1: Use bootrec

To use the bootrec utility and fix the boot error of your Windows 7 system, follow these steps:

If you don’t have the Windows 7 installation CD/DVD to run Command Prompt, go to Fix UEFI Boot with Easy Recovery Essentials.


  1. Insert the original Windows 7 installation CD/DVD and boot from it
  2. Select a language, keyboard and click Next
  3. Select the operating list (Windows 7) from the list and click Next
  4. At the System Recovery Options screen, click Command Prompt
    Windows 7 System Recovery Options Screen

    Windows 7 System Recovery Options Screen

  5. Type: bootrec /fixmbr
  6. Press
  7. Type: bootrec /fixboot
  8. Press
  9. Type: bootrec /ScanOs
  10. Press
  11. Type: bootrec /rebuildBcd
  12. Press
  13. Remove the installation CD/DVD, type exit, press and restart your computer
Windows 7 bootrec utility results screen

Windows 7 bootrec utility results screen

If the bootrec utility doesn’t fix the boot error, follow Fix #2: Use diskpart.

Fix #2: Use bootsect

Windows Setup CD/DVD Required!
Some of the solutions below require the use of the Microsoft Windows setup CD or DVD. If your PC did not come with a Windows installation disc or if you no longer have your Windows setup media, you can use Easy Recovery Essentials for Windows instead. EasyRE will automatically find and fix many problems, and can also be used to solve this problem with the directions below.

Follow these steps to run diskpart to repair the boot sector code of the Windows 7 installation:

  1. Follow the steps from Fix #1: Use bootrec until you reach Command Prompt
  2. Type: bootsect /nt60 SYS /mbr
  3. Press
  4. Remove the Windows 7 installation CD/DVD from the disc tray, type in Command Prompt and press
  5. Restart your computer
Windows 7 bootsect utility results screen

Windows 7 bootsect utility results screen

Fix UEFI Boot in Windows 8, 8.1 or 10

To fix the UEFI bootloader on a Windows 8, Windows 8.1 or Windows 10 system, you can follow these options:

Fix #1: Use diskpart

If the UEFI partition on your computer doesn’t have a drive letter assigned, this may be the primary cause of your computer’s boot error.

A common is to use the diskpart utility (available on the Windows 8/8.1/10 recovery disc/USB) to make sure the UEFI partition has a letter assigned to it. If it doesn’t, you’ll assign it a letter.

Windows Setup CD/DVD Required!
Some of the solutions below require the use of the Microsoft Windows setup CD or DVD. If your PC did not come with a Windows installation disc or if you no longer have your Windows setup media, you can use Easy Recovery Essentials for Windows instead. EasyRE will automatically find and fix many problems, and can also be used to solve this problem with the directions below.

The instructions you need to follow are:

  1. Insert your original Windows 8/8.1/10 installation disc or installation USB
  2. Boot from the disc or the USB
  3. At the Install now screen, click Repair your computer or press
    Windows 8 Repair Your Computer Menu

    Windows 8 Repair Your Computer Menu

  4. Click Troubleshoot
  5. Click Advanced options
  6. Click Command Prompt
  7. When Command Prompt has finished loading, type: diskpart
  8. Press
  9. The diskpart utility should now be loaded: DISKPART>
  10. Type: sel disk 0
  11. Press
  12. Wait for the confirmation message: Disk 0 is now the selected disk.
  13. Type: list vol
  14. Press
  15. diskpart will now show the full list of volumes available on your PC
  16. Find the UEFI volume from the list. This usually has “BOOT” mentioned on the Label column, “System” on the Info column. The Fs column might FAT32 specified.For our example, in the next steps, our UEFI partition will be on Volume 2.
  17. Type: sel vol 2
  18. Press
  19. Type: assign letter=G:

    Where should be a unique drive letter. It can’t be already used, e.g. C:\, D:\

  20. Press
  21. Wait for the confirmation message: DiskPart successfully assigned the drive letter or mount point.
  22. Type: exit
  23. Press
  24. Type: cd /d G:\EFI\Microsoft\Boot\

    Where is the drive letter you’ve assigned to your UEFI partition a few steps back. If the folder doesn’t exist (the error message will be “The system cannot find the path specified”), you can run the same command on alternative paths:

    cd /d G:\Boot\


    cd /d G:\ESD\Windows\EFI\Microsoft\Boot\

    Remember to replace with the UEFI’s partition letter.

  25. Type the bootrec command: bootrec /fixboot

    NOTE: on newer Windows 10 installs this command may return with an “Access Denied” error. On those versions the following command should be run:

    bcdboot C:\windows /s V: /f UEFI
  26. Press
  27. For backup purposes, backup the BCD record of your computer like this: ren BCD BCD.bak
  28. Recreate the BCD using the bcdboot command: Bcdboot C:\Windows /l en-us /s x: /f ALL

    Where is the letter of the drive where Windows 8, Windows 8.1 or Windows 10 is installed on. The parameter is used for localization: US. You can use for UK localization.

  29. Press
  30. You can also run this command too: bootrec /rebuildbcd
  31. Press
  32. Type in Command Prompt
  33. Restart your computer
  34. Your Windows 8/8.1/10 should now boot again
Windows 8 bootrec utility results screen

Windows 8 bootrec utility results screen

Fix #2: Use Automatic Repair

The built-in Automatic Repair utility, available on the Windows 8, Windows 8.1 or Windows 10 disc, might fix errors with the UEFI bootloader of your computer.

In most cases, Fix #1: Use diskpart works better than Fix #2.

Windows Setup CD/DVD Required!
Some of the solutions below require the use of the Microsoft Windows setup CD or DVD. If your PC did not come with a Windows installation disc or if you no longer have your Windows setup media, you can use Easy Recovery Essentials for Windows instead. EasyRE will automatically find and fix many problems, and can also be used to solve this problem with the directions below.

The instructions to run Automatic Repair are:

  1. Insert the Windows 8/8.1/10 installation disc or USB
  2. Restart your computer and boot from disc/USB
  3. At the Install Now screen, click Repair your computer
  4. At the Choose an option screen, click Troubleshoot
  5. Click Automatic Repair
  6. Choose an account from the list to continue, at the Automatic Repair screen
  7. Wait for the process to finish
Windows 8 recovery options screen

Windows 8 recovery options screen

More Information

Linked Entries

Support Links

Applicable Systems

This Windows-related knowledgebase article applies to the following operating systems:

  • Windows 7 (all editions)
  • Windows 8 (all editions)
  • Windows 8.1 (all editions)
  • Windows 10 (all editions)

Propose an edit

Sours: https://neosmart.net/wiki/fix-uefi-boot/

You will also like:

How to Repair EFI/GPT Bootloader on Windows 10?

In this article we will learn how to repair Windows bootloader on a modern computer that uses UEFI instead of BIOS and GPT disk partition table (instead of MBR). The corruption of the Windows bootloader can occur after installing a second OS (in Dual Boot configurations), incorrect actions during Windows recovery, removal of some data on hidden partitions, malicious software (virus, ransomware, etc.) and for some other reasons.

This article provides a step-by-step guide for recovering a damaged or deleted bootloader on Windows 10 and Windows 8.1 on computers running in native (non-legacy) UEFI mode. The guide should help if Windows doesn’t boot due to missing or damaged boot configuration file \EFI\Microsoft\Boot\BCD.

The boot configuration data for your PC is missing: EFI\Microsoft\Boot\BCD

A computer with Windows 10 installed in native UEFI mode will fail to boot if the EFI bootloader is corrupted. When trying to boot the computer, the following BSOD (Blue Screen of Death) error appears:

The boot configuration data for your PC is missing or contains errors. File :\EFI\Microsoft\Boot\BCD Error code: 0xc000000f


Error code: 0xc000014c

boot configuration errors 0xc000000f or missing file \EFI\Microsoft\Boot\BCD

This error indicates that the Windows bootloader configuration – Boot Configuration Data (BCD) has been corrupted or even completely removed. If you try to repair the bootloader on a UEFI computer using the tool, you will receive an error like this:

The boot configuration data store could not be found. The requested system device cannot be found.

The fact is that if Windows 10 is installed in native UEFI mode on a GPT disk, then the Windows 10 EFI bootloader (Windows Boot Manager) stores the boot manager and BCD configuration on a separate hidden EFI volume (100 MB in size with the FAT32 file system). The bcdedit tool doesn’t see this EFI partition, and cannot manage the bootloader configuration on it.

If the computer boots with a black screen with the message “Operating System not found”, most likely the Windows bootloader is completely removed. Follow the instructions on the link.

Automatic Windows Bootloader Recovery

The procedure for the automatic repair of the bootloader used in the Windows Recovery Environment (WinRE), is usually useless in such cases. But it’s worth a try anyway:

  1. Try to boot your device from the recovery disc or installation Windows 10 media;
  2. On the installation screen, click the Restore System;
  3. Then select Troubleshoot -> Startup Repair and select the OS whose bootloader you want to try to recover;windows10 Startup Repair menu
  4. But most likely the result will be negative: . Automatic Repair Couldn’t Repair Your PC

Using BCDBoot to Manually Repair EFI Bootloader in Windows 10

Let’s move on to the procedure for manually restoring the EFI Windows bootloader on a computer with UEFI.

To repair the bootloader configuration (BCD), you have to boot from the original installation Windows 10 media (or a recovery disk or a special UEFI bootable USB flash drive). After booting into the recovery environment, you need to open a command line: select System Restore – > Troubleshoot-> Command Prompt).

You can run Command Prompt if you only have a Windows installation media at hand. To do this, on the first screen of Windows installation (when choosing a language and keyboard layout), press the key combination Shift+F10 (or Shift+Fn+F10 on some laptop models).

system restore mode win 8

In the command prompt that opens, run the disk management tool by typing the command:

Display the list of drives on the computer:

At this stage, it is very important to determine the type of partition table on the disk on which Windows is installed: MBR or GPT. The point is that the EFI bootloader is used only on disks with a GPT partition table.

If the disk has an asterisk () in the Gpt column, then the GPT partition table is used, if not, the MBR is used.

diskpart: GPT or MBR - checking disk partition table

If your disk uses a GPT partition table, follow the steps below in the instructions to repair the Windows EFI bootloader.

If you have an MBR partition table on your disk, this instruction won’t work for your computer. Most likely you have a computer with BIOS or Legacy/Compatibility Support Mode (CSM) option enabled in the UEFI settings.

On MBR disks, the Windows bootloader is stored on a separate System Reserved partition, not on an EFI partition (in any case, don’t convert the MBR partition table to GPT until you fix the Windows bootloader !!). Use another guide to restore the BCD bootloader on MBR (Master Boot Record) disk.

Select the disk with Windows installed (if there is one hard disk in the system, its index should be 0):

Display the list of partitions and volumes on the disk:

diskpart : list volume . efi volume

In this example, you can see that the EFI boot partition (it can be easily identified by the size of 100 MB, and the FAT32 file system, most often its label is System EFI) has the partition 2 index (aka Volume 5 with the Hidden label). The main partition with the installed Windows with the NTFS file system (it can be both Windows 10 and Windows 8.1) is volume 2. There must also be an MSR (Microsoft System Reserved) partition of 16 MB for Windows 10 (or 128 MB for Windows 8.1).

Assign the drive letter K: to the hidden EFI volume:

A message that the drive letter has been successfully to the EFI partition should appear:

DiskPart is successfully assigned the drive letter or mount point.

Close the diskpart:

Go to the bootloader directory on the hidden volume:

In this case, K: is the drive letter assigned to the EFI partition just above. If the \EFI\Microsoft\Boot\ directory is missing (error The system cannot find the path specified), try the following commands:


At this point, many guides recommend running the following commands, which should overwrite the partition boot record, find the installed Windows and add them to the BCD:

or even:
(recovering MBR record for a GPT disk looks strange)

All of these commands are applicable only for disks with MBR. If your computer boots in UEFI mode, then it necessarily uses the GPT partition table (as in our case). Therefore, when you run commands, you will see an error:

To fix boot records on an EFI partition, you need to use the tool. The BCDBoot tools allows you to restore bootloader files on the system partition by copying them from the system directory on the Windows partition. The BCD bootloader configuration is recreated using the file.

Use the attrib command to remove the hidden, read-only, and system attributes from the BCD file:

Delete the current BCD configuration file by renaming it (this will keep the old boot configuration as a backup):

Using the bcdboot.exe utility, you need to recreate the BCD store by copying the UEFI boot environment files to the boot partition from the Windows directory:

  • C:\Windows – is the path to the directory with Windows 10 installed;
  • /f ALL – means that you want to copy the Windows Boot Environment files, including those for UEFI and BIOS computers (potential ability to boot in UEFI and BIOS systems). To copy only the EFI bootloader, use the /f UEFI command;
  • /l en-us — is a type of the system locale. By default, en-us – English (USA) is used;
  • /c – this is a new BCDBoot option in Windows 10 that allows you to overwrite existing boot records (including debugsettings). Use this option to ignore old boot settings and create a clean BCD configuration;
  • /v – used to enable BCDBoot verbose output.
Hint. If you use a localized version of Windows 10, the command will be different. For example, in the Windows version for the UK, use the following command

Windows 10 Dutch:

Windows 10 Deutch (German):

Now, if you run the command, you will see the following :

An entry should appear in the Windows Boot Manager section containing the full path to the UEFI boot file (). In this example, it is located on volume 2 ().

bcdedit: windows boot manager bootmgfw.efi

Possible errors:

  • BFSVC Error: Could not open the BCD template store. status – [c000000f] – check if the entered command is correct and whether you have a localized Windows version installed. In this case you need specify the correct local language code. The bcdboot tool copies the BCD template files from the \Windows\System32\Config directory. If the BCD templates in this folder are damaged or deleted, try to check the integrity of the system files offline using the tool (you need a Windows installation disc – drive D :):
  • BFSVC Error: Error copying boot files from Last Error = 0x570 – try to check drive with the help of command:
  • BFSVC Error: Failed to set element application device. Status = [c000000bb] – check the EFI and Windows 10 partitions with . Verify that the hidden and system attribute of the BCD file is cleared. Remove it:

    bcdboot: bfsvc error
  • Failure when initializing library system volume – make sure you are using the correct FAT32 partition with EFI (you may have several similar partitions).

Now you need to restart your computer and disconnect the bootable media. Then the Windows Boot Manager appears in the list of bootable devices, where you can choose desired operating system to boot. Your EFI bootloader and BCD configuration have been restored successfully!

Sours: http://woshub.com/how-to-repair-uefi-bootloader-in-windows-8/

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