What should I do to fix Win10 BCD? 4 easy methods to fix!

What is BCD in Win10?
Before understanding the Win10 BCD repair method, we need to be clear about what BCD is. In the Windows 10 operating system, BCD represents Boot Configuration Data, which tells the Windows boot loader where to find boot information during runtime. Therefore, it is crucial for successfully loading and running the operating system.

So where do BCD files usually exist in Windows 10? It is stored in a file named “\ Boot” in the folder. The complete path of this file is “C (active partition) \ Boot \ BCD”.

For UEFI booting, the BCD file is located on the EFI system partition in “/EFI/Microsoft/Boot/BCD”. For traditional BIOS booting, the BCD file is located in the “/boot/BCD” of the active partition.

In what situations can BCD files be damaged?
In some cases, you may damage BCD files as follows:

Expand system activity partitions;
Unexpected shutdown;
Blue screen or other errors that require a restart;
Hard disk failure;
Virus attacks.
Usually, when the BCD is damaged or incorrect, it can cause Windows 11/10/8/7 to fail to start and prompt the following error message:

Your computer/device needs repair: Your computer’s boot configuration data is missing or contains errors. File: \ Boot \ BCD Error code: xc000000 f.

Windows cannot start: The reason may be due to recent hardware or software changes. File: \ Boot \ BCD Status: xc000000 f Information: Error attempting to read boot configuration data.

The device connected to your computer is experiencing an unexpected I/O error with error code 0xc00000e9.

Your computer needs repair: The boot configuration data file does not contain valid information for the operating system, File: \ Boot \ BCD Error code: xc0000098.

File: \ Boot \ BCD Status: 0xc0000034 Info. The Windows boot configuration data file is missing necessary information.

So, what should we do to fix the BCD boot file for Win10? Next, we will gradually introduce four methods for repairing BCD files to you.

Four methods for repairing Win10 BCD!
Many users do not know how to perform Win10 BCD file reconstruction, so in this section, we will gradually show you four methods for Win10 BCD repair.

Note: If you have a Windows installation CD, you can try the first three methods by manually repairing BCD using the command prompt. If there is no Windows installation disk, you can skip to method 4 and repair it using a professional Win10 BCD repair tool.

✔ Method 1. Use startup repair for repair
The startup repair option in the Windows recovery environment can repair damaged BCD files. Please follow the following steps to repair:

1. Insert the Windows 10 installation disk into the computer and start the computer from that media.
2. Continuously press the F2 or DEL keys (the keys may vary depending on the computer manufacturer) to enter BIOS.
3. Change the startup order so that the computer starts from the installation CD.
4. Select language, time, currency, keyboard, and input method, and then click “Next”.

Choose language, time, currency, keyboard, and input method

5. Click “Repair Computer”.

Repair computer

When the “Select an option” menu opens, select “Troubleshooting”.

Troubleshooting

7. Select “Advanced Options” in the “Troubleshooting” window.
8. Then select “Start Repair” to perform the relevant repairs.

Start repair

After completing these steps, starting repair will start scanning, detecting, and repairing any issues that may prevent Windows 10 from loading correctly. Afterwards, you can check if Windows 10 can start normally, and if so, the problem has been resolved.

✔ Method 2. Use Bootrec. exe tool to rebuild BCD
If the repair method cannot repair the BCD file, you can use the Bootrecxe tool in the Windows Recovery Environment (Windows RE) to rebuild the BCD file.

1. Access the command prompt from the Windows installation CD, and select “Command Prompt” from the “Advanced Options” screen.

command prompt

2. In the command prompt window, enter the following command:

Bcdedit/export C: \ BCD_Backup
Ren c: \ boot \ bcd bcd.old
Bootrec/rebuildbcd
Note: C: is the drive letter where the BCD file is located, usually the system disk. You can use DiskPart to view the drive letter of your system disk.

✔ Method 3. Use the command prompt to repair BCD
If the above method does not work, you can try other commands to fix Win10 BCD. Enter the following commands in sequence at the command prompt:

Bootrec/fixmbr
Bootrec/fixboot
Bootrec/rebuildbcd
Fix BCD

✔ Method 4. Repair through Aomei Partition Assistant (Recommended)
How to fix BCD errors during Win10 startup? You can first use Aomei Partition Assistant to create a USB boot disk, and then repair the BCD. Aomei Partition Assistant is a free disk management tool that supports operating systems such as Windows 11/10/8/7 and Windows XP/Vista, as well as the Windows Server system.

Before entering the specific operation steps, we need to do some preparatory work. Please prepare an empty USB drive (at least 16GB) for creating a USB boot disk and a computer that can start normally, then download and install the Aomei Partition Assistant on this computer.

Free download

Win 11/10/8.1/8/7/XP

1. Connect the USB drive to a Win10 computer that can start normally and run the Aomei Partition Assistant. Click on “Create Startup Disc” in the left wizard on the main interface, and then click “Next”.

Creating a startup disc

2. Check “USB boot device”, click “execute”, and then follow the instructions to create a Windows 10 bootable media.

USB boot device

3. Then connect the prepared USB flash drive to the damaged Win10 system computer and start the computer from the USB flash drive. The Aomei Partition Assistant will automatically start when the computer starts.
4. Right click on the system hard drive and select “Rebuild MBR” from the drop-down menu.

Rebuild MBR

5. Select the appropriate MBR type for your current operating system, and then click “OK”.

Choose the appropriate MBR type

6. After returning to the main interface, click “Submit”>”Execute” in the upper left corner to repair the Windows 10 BCD file.

Fix Windows 10 BCD files

summarize
Now, you can choose the appropriate method to repair Win10 BCD according to your own situation. In contrast, the Aomei partition assistant is simpler to operate, and it can also fix issues such as BOOTMGR loss and other inability to start.

Of course, if you need to format partitions, adjust partition sizes, or merge partitions without deleting data, you can use the Aomei Partition Assistant for disk related operations, and these functions are all free. If you are interested, come and download to experience it!