Missing Windows Boot Manager or bootrec fixboot error

The “bootrec /fixboot access denied” error in Windows occurs when the bootrec /fixboot command cannot access or modify the boot sector and similarly Windows Boot Manager missing in the BIOS Boot Order are often due to issues with the Boot Configuration Data (BCD) or partition structure.

To resolve this, try using bcdboot to rebuild the BCD store, or attempt to fix the issue using the Windows Recovery Environment

Here’s a breakdown of how to troubleshoot and resolve the issue:

1. Boot into Windows Recovery Environment (WinRE):

• Using F8:
  Restart your computer and press F8 repeatedly during startup to access the Advanced Boot Options. Select “Repair Your Computer”.
• Automatic Repair:
  If you can’t access WinRE via F8, repeatedly turn your computer on and off (about three times) until it automatically enters the repair environment.

2. Access Command Prompt:

• In WinRE, navigate to Troubleshoot > Advanced Options > Command Prompt.

3. Identify and Select Boot Volume:

• Open Diskpart: Type diskpart and press Enter.
• List Disks: Type list disk to see a list of your hard drives.
• Select Boot Drive: Identify the disk containing your Windows installation (usually Disk 0) and select it using select disk 0.
• List Volumes: Type list vol to see a list of partitions on the selected disk.
• Select System Partition: Identify the EFI partition (typically around 260MB) and select it using select vol 1 (replace 1 with the actual volume number).
• Assign Drive Letter: Assign a drive letter to the partition using assign letter=b:(or any available letter).
• Exit Diskpart: Type exit.

4. Rebuild BCD and Rewrite EFI Bootloader:

• Change to Boot Directory: Navigate to the EFI/Microsoft/Boot directory using cd /d b:\EFI\Microsoft\Boot\.
• Rename the existing BCD file as a backup using ren BCD BCD.bak.
• Use the bcdboot command to recreate the BCD store and rewrite EFI Bootloader:
  bcdboot c:\Windows /l en-us /s b: /f ALL (adjust assigned drive letter as needed).

5. Reboot and Check:

• Type exit to close the command prompt.
• Reboot your computer and see if the issue is resolved. You may need to adjust the boot order in the BIOS settings to boot from your hard drive.

Alternative Solutions:

1. Startup Repair:

• In WinRE, you can also try running Startup Repair under Troubleshoot > Advanced Options, which attempts to automatically fix boot problems

2. Bootsect:

• If bootrec /fixboot fails with access denied error , try using the bootsect /nt60 all command before running bootrec /fixboot. This command updates the master boot code