Fix Boot Error 0xC0000034 (The Windows Boot Configuration Data file is missing required information)

Boot Error 0xC0000034 (The Windows Boot Configuration Data file is missing required information) is caused by missing self-referencing Boot Manager entry in the BCD registry hive.

Error 0xC0000034 (status 0xC0000034) can be fixed by rebuilding Boot Configuration Data registry hive from scratch using Emergency Boot Kit.

1. Symptoms of the problem

When computer is powered up, the following error message appears:

File: \Boot\BCD
Status: 0xC0000034
Info: The Windows Boot Configuration Data file is missing required information

2. Cause of the problem

The rest of this article refers to Windows 7, but all information below applies to Windows 10/11 as well.

BCD hive with status 0xC0000034 differs from BCD hive without status 0xC0000034 in one subtle detail: it has no {bootmgr} entry (which is stored as raw BCD object with constant GUID {9dea862c-5cdd-4e70-acc1-f32b344d4795}).

Raw BCD hive with status 0xC0000034:

Raw BCD hive without status 0xC0000034:

3. How to fix status 0xC0000034

1) Download Emergency Boot Kit and deploy it to USB thumbdrive according to the instructions, then set up your BIOS to boot from USB thumbdrive. You need full version of Emergency Boot Kit to actually write changes to the disk, but it's recommended to try demo version to make sure  there are no hardware incompatibilities.

2) Boot into Emergency Boot Kit:

3) Run File Manager from the main menu:

4) Press Alt+F1 and choose your boot partition from the menu. In Windows 7 and Windows 8 boot partition has size about 100MB in size and "System Reserved" volume label. In Windows Vista separate boot partition does not exist, computer boots from system disk where Windows OS files are installed (use UP and DOWN arrow keys and ENTER to navigate the menu):

5) Now you need to enter either Boot folder (on BIOS-based computers) or EFI\Microsoft\Boot (on UEFI-based computers). Only one of these folders exists on any particular computer, so choose whatever exists.
Press TAB to switch input focus to the left panel, then navigate folders using arrow keys UP and DOWN and ENTER. (This example shows entering Boot folder.)

6) List of files should appear on the left panel. BCD file should be in the list, BCD.LOG, BCD.LOG1 and BCD.LOG2 may also appear in the list. Navigate to those files using arrow keys, then select them INSERT key:

7) After selection:

8) Press F6. File rename dialog will pop up:

9) Type BCD_OLD.* on keyboard and press ENTER:

10) Make sure BCD files were renamed successfully to BCD_OLD files, then press F10 and ENTER keys to exit the Emergency Boot Kit File Manager:

11) Choose Mount & Boot Center in the main menu:

12) Wait:

13) Enable checkbox (checkboxes) on the intersection of the bootloader and operating system (operating systems) it should load:

14) Mount & Boot Center should look like below. Press OK to commit changes (BCD registry hive and corresponding log will be created from scratch at this point):

15) "Status 0xC0000034" boot problem should be fixed now. Choose 'Reboot' in the main menu of Emergency Boot Kit:

Please note: Because BCD (Boot Configuration Data) was recreated from scratch, you may need to adjust boot timeout, menu order etc from within Windows when it boots successfully.