Fix Windows Error 0xc0000034 - BCD Missing Boot Files

You are staring at a blue screen telling you that your BCD file is missing, and your PC refuses to boot. This usually happens after a failed update or a sudden crash has corrupted your boot configuration, but we can fix it by repairing those files from a Windows installer.

Why this happens

The error 0xc0000034 indicates that the Boot Configuration Data (BCD) file is either corrupted or missing, preventing Windows from locating the files needed to start your system.

What you'll need

You will need a second working computer and a USB flash drive with at least 8GB of space to create a Windows installation media.

Steps

1. 01
   Download the Windows Media Creation Tool from Microsoft and use it to turn your USB drive into a bootable installer.
2. 02
   Insert the USB into the broken PC, power it on, and tap your BIOS key (usually F2, F12, Delete, or Esc) to set the USB as the primary boot device.
3. 03
   Once the Windows installer loads, select your language, click Next, and then click Repair your computer in the bottom-left corner.
4. 04
   Navigate to Troubleshoot > Advanced Options > Command Prompt.
5. 05
   Type diskpart, then list volume to identify the letter of your main Windows drive (look for the largest NTFS volume), then type exit.
6. 06
   Run the following commands in order: bootrec /scanos, bootrec /fixmbr, bootrec /fixboot, and bootrec /rebuildbcd.
7. 07
   If bootrec /fixboot returns 'Access is denied', run bootsect /nt60 sys then try bootrec /rebuildbcd again.
8. 08
   When asked to add the installation to the boot list, type Y for the entry pointing to /Windows.
9. 09
   If you see 'The requested system device cannot be found', return to diskpart, list volume, and find the small FAT32 partition (100-500MB).
10. 10
    Select that volume with select volume [number], assign it a letter using assign letter=B, then type exit.
11. 11
    Run bcdboot C:/windows /s B: /f UEFI (replace C if your Windows drive letter was different).
12. 12
    Type exit, click Continue, and remove the USB drive as the system restarts.