Boot Configuration Data Missing: Fixes That Work

If your PC shows “Boot configuration data for your PC is missing or contains errors,” Windows cannot find the Boot Configuration Data (BCD) store that tells it how to start. You can usually fix this yourself using Windows Recovery Environment (WinRE) and a few command-line tools, without reinstalling Windows.

What Is the Boot Configuration Data?

The BCD store is a small database that Windows uses to load the operating system. It contains entries for each installed OS, boot parameters, and paths to boot files like winload.exe. On modern UEFI systems, the BCD lives on the EFI system partition (ESP), while on older BIOS systems it is in the active partition, usually C:\Boot\BCD. If Windows can’t read this store, it stops with the error “Boot configuration data for your PC is missing or contains errors.” The same error can appear with a code like 0xc000000f.

Why Does This Error Happen?

Common causes include:

• Corrupted or deleted BCD files after a failed update or power cut.
• Disk errors on the system or boot partition.
• Misconfigured boot order in BIOS/UEFI.
• Third-party partitioning tools or dual-boot setups gone wrong.
• Malware that targets boot records.

The error usually appears immediately after the POST screen, before Windows starts loading. You might still see the Windows logo briefly, then the blue screen with the error text.

How to Access Windows Recovery Environment

To fix the BCD, you need to boot into WinRE. If Windows fails to start several times, it should automatically enter WinRE. If not, use a Windows installation USB or recovery drive:

1. Insert the USB and boot from it (press F12, Esc, or Del during startup to choose boot device).
2. Select your language, then click “Repair your computer” at the bottom-left.
3. Choose Troubleshoot > Advanced options > Command Prompt.

If you don’t have a USB, you can try pressing Shift+F8 repeatedly during boot, but this rarely works on modern Windows due to fast startup.

Step-by-Step Fix: Rebuild the BCD

Once in Command Prompt, run these commands one by one, pressing Enter after each. They work for both BIOS and UEFI systems:

1. bootrec /fixmbr – repairs the master boot record (BIOS) or the protective MBR on GPT disks.
2. bootrec /fixboot – writes a new boot sector. If you get “Access is denied,” skip to the next step.
3. bootrec /scanos – scans for Windows installations.
4. bootrec /rebuildbcd – rebuilds the BCD store. When asked to add the installation, type Y and press Enter.

After these, type exit and restart your PC. If the error is gone, you’re done.

If bootrec /rebuildbcd Fails

Sometimes the BCD store is too damaged for bootrec to rebuild. In that case, you can manually delete and recreate it. First, find the drive letter of the EFI partition (on UEFI) or the system partition (on BIOS). In Command Prompt, type:

diskpart
list disk
select disk 0
list partition

Look for the partition labeled “System” (usually 100–500 MB). Note its number, then type select partition 1 (replace 1 with the actual number), then assign letter=S. Type exit to leave diskpart.

Now, for UEFI systems, run:

cd /d S:\EFI\Microsoft\Boot
ren BCD BCD.old
bootrec /rebuildbcd

For BIOS systems, the path is usually C:\Boot. If you get an error that the folder doesn’t exist, your system may be UEFI; try the EFI path instead.

Other Fixes to Try

If rebuilding the BCD doesn’t work, try these in order:

• Check disk errors: Run chkdsk C: /f /r (replace C: with your Windows drive letter). This can take a while.
• Run System File Checker: Type sfc /scannow after booting into WinRE. Note that it may not work perfectly offline.
• Reset BIOS/UEFI settings: Restart, enter BIOS (usually F2 or Del), and load default settings. Make sure the boot mode matches your disk (UEFI vs Legacy).
• Use Startup Repair: In WinRE, go to Troubleshoot > Advanced options > Startup Repair. It sometimes fixes BCD issues automatically.

If none of these work, you may need to reinstall Windows, but you can often back up your files first by booting from a USB and copying them to an external drive.

Frequently Asked Questions

Will I lose my files if I fix the BCD?

No. The commands above only repair boot files and the BCD store. Your personal files, documents, and installed programs remain untouched. However, if you need to reinstall Windows to fix the problem, you may lose files unless you back them up first.

What does “Boot configuration data for your PC is missing” mean?

It means Windows cannot read the BCD store, which contains the instructions for loading the OS. Without it, Windows doesn’t know which boot files to run, so it stops with this error.

Can I fix this without a Windows installation USB?

Sometimes. If Windows automatically enters Recovery Environment after a few failed boots, you can use Command Prompt from there. If not, you’ll need a USB or recovery drive. You can create one on another PC using Microsoft’s Media Creation Tool.

Why did this happen after a Windows update?

Updates can sometimes corrupt the BCD if the system loses power during installation or if the update itself has a bug. Disk errors or a failing hard drive can also cause corruption.

Is this error the same as “bootmgr is missing”?

They are similar but different. “bootmgr is missing” means the boot manager file itself is missing, while the BCD error means the configuration data is missing or unreadable. Both are boot-related and can often be fixed with similar commands.

How long does the fix take?

Running the bootrec commands takes about 5–10 minutes. If you need to run chkdsk or sfc, add another 20–60 minutes depending on your hard drive size and speed.

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in bcd | BCD store drive | - | C |  | 
in fix | Fix type | Auto=1, Manual=2 | 1 | 1 | 2
out status | Fix status | - | if(fix=1, "Run bootrec /rebuildbcd", "Run bootrec /fixmbr") | 0