How to Repair Windows 11 UEFI Bootloader [Full Guide]

UEFI (Unified Extensible Firmware Interface) is a firmware extension that reads entries from a disk partition to boot Windows, serving as an interface between the operating system (OS) and the platform firmware. The Windows UEFI boot loader is responsible for loading the Windows OS and initializing other devices on your laptop. If the UEFI boot loader gets corrupted or malfunctions, you won't be able to start Windows unless you perform a recovery.

To fix this issue, you need to point to the EFI boot file and copy it to the EFI/Microsoft/Boot directory. This article will explore various methods that can resolve this problem.

Please provide the English content you'd like translated, I'll do my best to translate it into Chinese for you.

For those unaware, UEFI is the modern form of BIOS. It provides more security and features.

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Repair UEFI Boot Errors in Windows 11 Using Diskpart

Since you can't start Windows, the only solution is to use Advanced Recovery. You'll need a bootable USB drive that you can create on another Windows computer. Download the Windows Media Creation Tool and use it for this purpose. Once that's done, make sure to set the first boot device in your UEFI or BIOS to the USB drive.

Enter recovery mode

When booted from the USB drive, it looks like a regular Windows installer. You need to click on the “Repair your computer” option in the bottom left of the install screen. This will get you to Advanced Recovery. Go to Troubleshoot > Advanced options > Command Prompt.

Locate the EFI partition

At the command prompt, enter the following command.

Here are the sentences translated into American English:
• diskpart
• Select disk 0
• List volume

In most cases, the EFI partition is typically found on the first disk, so we use the command `Select Disk 0`, followed by `list vol` to list the partitions or volumes.

It should display a list of partitions, including hidden ones, in File Explorer. Look for a volume labeled EFI.

Assign a drive letter to the EFI partition

Since the EFI partition has no drive letter assigned to it, it remains hidden. Moreover, you would need to assign a drive letter to it if you want to perform any operations. You can do this by following these steps:

Assign drive letters to EFI partitions Select the image

• Select docket
• Assign letters

First, select the partition or volume. In this case, it's the EFI partition or volume number 2. Next, assign an unassigned drive letter. Choose a random letter, like Q or R, or any letter that isn't on the list.

Type exit, and then press ENTER to close the Diskpart tool and return to the command prompt.

"Repair Boot Record"

Next, you need to enter the EFI partition and use the following command to fix the boot record:

• Switch to the /d directory
• Run the command bootrec /FixBoot
• Rename the BCD file to BCD.bak
• Use the bcdboot command: C:\Windows /l en-us /s x: /f ALL
• Run the command bootrec /rebuildbcd

Now that we've used the BCDBoot command to replace the new BCD file and used the bootrec command to rebuild it, we're all set.

Alright, just restart your computer now, remove the USB device, and let Windows start normally. As you can see, Diskpart can be a bit complex, so please share this tutorial to help users who might not be that experienced with computers.

Repair your computer using the Windows installation disc/USB

The Windows Advanced Recovery Mode offers an automatic repair option that can also fix such issues.

Create bootable media.

Download the Windows Media Creation Tool, and use it to create a bootable USB drive. This tool contains a suite of programs that can help you recover your computer in the event of a system crash. Then, insert the device and boot your computer from USB.

Advanced Recovery - Auto Repair

When it boots from the USB, it will look like a Windows installation. When it comes up, choose “Repair your computer” to get to the Advanced Recovery options.

Click on “Troubleshoot” > “Advanced options” > “Startup Repair”. It should fix any corrupted EFI bootloader issues.

How to change the boot mode to UEFI to install Windows 11

It's possible that your motherboard supports UEFI but is still using Legacy BIOS mode. Windows 11 doesn't support older firmware, so you'll need UEFI. However, switching your boot mode to UEFI is straightforward.

Step 1: Press the 'Win' + 'I' keys to open Settings, then go to Update & Security > Recovery > Advanced startup, and click on 'Restart now.'

Step 2: In Advanced Recovery, click Troubleshoot > Advanced options > UEFI Firmware Settings.

Step 3: Click on “Restart,” which should take you to your motherboard's UEFI settings. Enable the recommended settings, and then restart your computer.

Convert MBR to GPT with Partition Master Tool

When using Windows 11, it's essential to have your partitions based on GPT rather than MBR. The system will warn you about this during the upgrade process. However, the major drawback of using built-in tools for the conversion is that they will format all your data. In this case, third-party software comes in handy.

"Partition Manager Tool" is a professional software that can assist you with all disk management-related operations. It can also convert an MBR partition to GPT without data loss. Here are the steps:

Step 1: Insert the blank USB drive or CD/DVD into a working computer. Launch Partition Master, click “Bootable Media”, then select “Create Bootable Media”. Click “Next” to continue.

Step 2. Select USB or CD/DVD, and then click "Create" to start creating the bootable media.

Step 3: Connect the USB with the bootable media to your computer, and then restart your computer from the bootable media tool.

Press F2 or Del to enter BIOS and set the computer to boot from "Removable Device" (boot USB drive) or "CD-ROM Drive" (boot CD/DVD). Press "F10" to save and exit, then restart your computer to access the tool from the boot media.

4. After you launch Partition Master, click “Disk Conversion,” then select “MBR to GPT.” Click “Next” to proceed.

Step 5: Select the MBR disk that you want to convert to GPT, and click "Convert" to start the conversion.

Conclusions

The requirements for Windows 11 are quite different from its predecessor. You might have recently bought a computer with UEFI and GPT support but are unsure how to enable and switch without losing your data. With professional software like the Partition Master tool, you can accomplish this easily. However, it's crucial to back up your data first.