[Fixed]: How do I Manually Rebuild BCD File on Windows 10?

When should we rebuild the BCD file?

The Boot Configuration Data (BCD) file is a crucial component for storing boot configuration data used by Windows operating systems. It contains the essential data needed for the operating system to initiate successfully. If the BCD becomes corrupted or misconfigured, the system can encounter boot failures or various errors.

In such cases, it is advised to repair BCD errors to restore the failed system to normal function. However, this method may not always be effective, particularly when encountering severe issues such as “Boot Manager is missing,” boot problems following an upgrade or new OS installation, or significant hardware changes. In these cases, creating a new BCD file may be necessary instead of simply repairing it.

“How do I manually rebuild the BCD file on Windows 10?” Keep reading this guide to discover how to rebuild the BCD on Windows 10 using Command Prompt and a third-party tool.

How do I manually rebuild BCD file on Windows 10?

When the BCD file becomes corrupted or misconfigured, you can manually rebuild it using bootrec commands. Bootrec is a command-line utility in Windows used for diagnosing and resolving boot-related issues. Follow these instructions to open Command Prompt and rebuild BCD on Windows 10.

Access the Windows Recovery Environment

Before rebuilding the BCD files, it is essential to enter the Windows Recovery Environment. Here are two practical ways to access WinRE when your computer cannot start up properly.

► Method 1. Use Bootable Media

Step 1. Create a bootable USB on another working computer, then insert it into your faulty PC.

Step 2. Turn on your computer and press F12 repeatedly to enter the boot menu. Then set it to boot from the USB drive.

Step 3. Select your language and other preferences, then click Next.

Step 4. Choose Repair your computer.

Step 5. Select Troubleshoot > Advanced options to see various recovery tools.

► Method 2. Trigger Automatic Repair

Step 1. Restart your computer by pressing and holding the power button.

Step 2. After repeating the process 2-3 times, it will enable the Automatic Repair to detect and fix boot issues.

Step 3. If Automatic Repair fails to resolve the boot-related issues, click the Advanced options to see more recovery tools.

Rebuild BCD on Windows 10 via Command Prompt

“How do I manually rebuild the BCD file on Windows 10?” Once you've accessed the WinRE, you can rebuild the BCD on Windows 10 using the bootrec commands. Follow these instructions to repair your system and resolve boot issues effectively.

Step 1. Select Command Prompt and input your account and password when required.

Step 2. Type bootrec /rebuildbcd and press Enter. It will trigger a search for Windows installations not included in the BCD store and prompt you to add them.

Step 3. If you get the following message, it means that Windows installation data in the BCD store exists but bootrec couldn't find any additional installations on your computer to add to the BCD. Move on to Step 6 to continue.

Step 4. If you get the following message, type Y or Yes to add installation to the boot list.

Step 5. Since the BCD store exists and lists a Windows installation, you'll first have to remove it manually and then try to rebuild it again. Input bcdedit /export c:\bcdbackup and press Enter to export the current BCD store to create a backup. Then you will be prompted that “The operation completed successfully.”

Step 6. Type attrib c:\boot\bcd -h -r -s and press Enter to remove hidden, read-only, and system attributes from the BCD file.

Step 7. Execute ren c:\boot\bcd bcd.old to rename the BCD store. Now you should be able to rebuild it, as you did in Step 5.

Step 8. Input bootrec /rebuildbcd and press Enter to rebuild the BCD again. Then you will be prompted that "Total identified Windows installations: 1 [1]...", which means the BCD store rebuild is progressing as expected.

Step 9. Type Y or Yes to add installation to the boot list. Then you will be prompted that “The operation completed successfully.”

Step 10. Restart your computer to check if it can start up correctly.

An Alternative Tool to Rebuild BCD

If you are unfamiliar with commands, using professional software like AOMEI Partition Assistant is an excellent alternative for rebuilding the BCD file. This powerful and comprehensive disk management tool includes rich features to troubleshoot common issues during regular tasks.

The integrated Boot Repair tool can automatically detect and repair various system boot issues, providing reliable repair solutions even if your computer won’t start normally. Feel free to download and explore the product via the link below.

Here’s how to rebuild BCD in Windows 10 using AOMEI Partition Assistant:

Step 1. Install AOMEI Partition Assistant on a working PC and connect a USB drive with enough storage to this PC.

Step 2. Open this software and select the Boot Repair tool below the Recover section.

Step 3. Click the create a bootable disk option to create a WinPE Boot Repair USB drive.

Step 4. Plug the created drive into the non-booting computer, then enter the BIOS settings to change the boot order so that the computer boots from it. It will automatically load the Boot Repair tool and perform a scan of boot entries.

Step 5. Once the process completes, you will see all scan results, including system paths, system versions, and boot status. Select the repairable boot entries you want to repair and click the Repair button.

Step 6. Wait for the repair process to finish, then remove the bootable USB drive and boot the PC from the original system drive.

Final Words

The Boot Configuration Data file is essential to Windows operating systems, but it can sometimes become corrupted or misconfigured, leaving various boot issues. How do I manually rebuild the BCD file on Windows 10? This guide walks you through the complete process of manually rebuilding the BCD file. Additionally, you can also use AOMEI Partition Assistant to further simplify the repair process.