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Difficulty: Very hardTroubleshooting Windows OS Startup and Boot Errors

A Windows 11 workstation utilizing a UEFI partition scheme fails to boot, displaying a blue screen with the error code 0xc000000f stating that the Boot Configuration Data (BCD) file is missing required information. A system administrator boots the system into the Windows Recovery Environment (WinRE) and opens the Command Prompt. Place the technician's recovery steps in the correct order to assign a temporary drive letter to the hidden EFI System Partition (ESP) and rebuild the BCD store.

  1. 1Launch diskpart and run list volume to identify the volume number of the FAT32 EFI System Partition.
  2. 2Select the EFI System Partition volume and execute assign letter=V: to mount it.
  3. 3Exit diskpart and navigate to the directory path V:\EFI\Microsoft\Boot\.
  4. 4Execute ren bcd bcd.old to back up the corrupt BCD file.
  5. 5Execute bcdboot C:\Windows /s V: /f UEFI to write fresh boot files to the EFI System Partition.

Answer

The correct sequence starts by opening Diskpart and listing volumes to locate the hidden FAT32 partition, selecting that volume and assigning it drive letter V:, exiting Diskpart to navigate to V:\EFI\Microsoft\Boot\, renaming the corrupted bcd file to bcd.old, and finally executing the bcdboot C:\Windows /s V: /f UEFI command to generate new boot files.
On UEFI systems, startup repair requires mounting the hidden FAT32 EFI System Partition via Diskpart. Once a letter is assigned, the technician must exit Diskpart to access the directory containing the BCD, rename the corrupt file so it does not block reconstruction, and run the bcdboot command referencing the Windows directory, target drive letter, and UEFI firmware type.

Step-by-Step Solution

1
Use Diskpart to identify the hidden EFI System Partition (ESP).
Discovers the specific volume formatted in FAT32 (typically around 100MB-500MB) that holds boot files.
On UEFI/GPT systems, boot files reside on a hidden partition without a default assigned drive letter.
2
Select the volume and assign a temporary drive letter (e.g., V:).
The hidden ESP becomes accessible via drive letter V:.
Command-line repair utilities require a valid drive path to modify or replace system boot files on the ESP.
3
Exit Diskpart and change working directory to V:\EFI\Microsoft\Boot\.
The terminal focus shifts directly to the location of the existing BCD file.
Operating within the boot directory allows manual backup and modification of boot files.
4
Rename the existing corrupt BCD store using ren bcd bcd.old.
The damaged BCD file is renamed, clearing the path for creating a clean BCD configuration.
If a damaged BCD file remains named 'bcd', repair utilities like bootrec or bcdboot may fail to overwrite it.
5
Run bcdboot C:\Windows /s V: /f UEFI.
Fresh system boot files and a valid BCD structure are created on the target volume.
The bcdboot utility extracts functional boot files from the main Windows OS installation directory and configures the UEFI bootloader properly.

Key Concept

Troubleshooting UEFI/GPT Windows OS Startup Errors via WinRE Command Line
Estimated Time:2m 30s
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Topics

Troubleshooting Windows OS Startup and Boot Errors

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