How to Fix the 0xc0000034 Error in Windows 10 [Practical Guide]

Windows stops loading when 0xc0000034 damages essential boot configuration data required for startup. Missing boot information prevents Windows from locating required startup files during initialization properly. Rebuilding the Boot Configuration Data store often restores missing startup entries, but additional repairs may be required if other boot components are damaged.

Some repair commands return additional errors requiring separate troubleshooting before Windows starts correctly. This guide explains each repair before covering data recovery and final options safely.

Part 1. What Error 0xc0000034 Means in Windows 10

Understanding this error first helps identify the correct repair before changing important startup components. Similar boot errors appear alike onscreen but describe different startup failures requiring separate repair methods.

What the Missing Boot Configuration Data Message Means

Boot Configuration Data stores startup information guiding firmware to locate Windows during every boot process. Windows Boot Manager reads this database before loading any Windows system files during startup operations. Missing required entries trigger a BCD error code 0xc0000034 before Windows loads successfully on startup. Windows opens the database but cannot find entries describing your installed operating system.

Database locations depend entirely on your computer firmware type and startup configuration settings used. UEFI stores BCD at “\EFI\Microsoft\Boot\BCD” inside the small FAT32 system partition by default. Legacy BIOS stores BCD at “\Boot\BCD” on the partition marked active for startup operations. Screen wording identifies firmware type, while different messages indicate separate causes requiring different repair methods.

Common Symptoms of Error Code 0xc0000034

Confirm the correct boot failure before repairing because similar startup errors often appear nearly identical together.

• Failure Before Windows Logo: Startup stops before the Windows logo, preventing installed system files from loading completely.
• Blue Recovery Screen: A blue recovery screen repeatedly appears, offering only a restart with identical error messages.
• Safe Mode Unavailable: Safe Mode remains inaccessible because Boot Manager controls both startup methods before Windows loads.
• BCD File Path Displayed: The message shows \BCD or \EFI\Microsoft\Boot\BCD, identifying firmware type immediately.
• No Automatic Recovery: Automatic recovery never starts, leaving installation media as the only remaining recovery option available.

Interrupted Windows updates commonly leave boot configuration changes unfinished, creating startup failures after restarting the computer. Disk operations like resizing, cloning, or deleting partitions often remove essential boot files needed during startup.

How 0xc0000034 Differs From 0xc0000098 and 0xc000000e

Several boot errors display similar recovery screens, making correct identification important before attempting repairs safely. The table below compares their messages, helping you identify the correct error before troubleshooting begins:

Read your screen against that middle column before choosing a fix. The wording is the only reliable way to tell which repair applies.

Part 2. How to Fix the 0xc0000034 Error

With the error identified, begin repairs inside Windows Recovery Environment using Windows 10 installation media first safely. Select “Repair your computer,” then complete each repair method below in the recommended troubleshooting order carefully.

Microsoft documents this repair sequence for error code 0xc0000034. Start by rebuilding the BCD store, then recreate Windows boot files before attempting additional repair methods afterward.

Fix 1. Run Startup Repair

Startup Repair automatically scans boot files and repairs common startup problems without requiring manual commands. It is the simplest repair because Windows performs the entire process automatically during startup recovery. Restart your computer after completion because some successful repairs require another boot before taking effect. Here is how you run Startup Repair:

Instructions. Pick “Troubleshoot” “Advanced Options” “Startup Repair” from the recovery menu. Choose your Windows installation > Let the diagnostic run. Give it a second attempt before moving on.

Fix 2. Rebuild the BCD Store With Bootrec

Bootrec scans the disks present, locates any Windows installation, and writes new entries describing what it turned up. That makes it the usual remedy when the store has lost its contents.

Step 1. In WinRE, enter “Troubleshoot” “Advanced options” “Command Prompt.” Then, run “bootrec /scanos.”

Step 2. After that, enter “bootrec /rebuildbcd” > Press “Y” when the installation is listed > Close the window and restart.

Fix 3. Recreate Windows Boot Files With BCDBoot

BCDBoot rebuilds damaged boot files when Windows 10 error code 0xc0000034 prevents successful startup. Microsoft states BCDBoot recreates system partition boot files using fresh Windows boot environment templates. To recreate boot files, use the simple steps below:

Step 1. In CMD, enter “diskpart” > “list volume.” Note the NTFS partition where Windows sits, and the FAT32 partition with a size of 100 to 500 MB.

Step 2. Enter “select volume 2” with FAT32 > Type “assign letter=V” > “exit.”

Step 3. Type “bcdboot C:\Windows /s V: /f UEFI.” Swap in your own Windows letter for “V:” > Restart.

Fix 4. Check the EFI System or System Reserved Partition

The BCD sits on a partition separate from Windows, and this error follows if that partition was deleted, resized, or left unformatted.

Step 1. Open DiskPart > Run “list volume.” On UEFI, find a 100–500 MB FAT32 partition. In Legacy BIOS, look for a System Reserved NTFS partition.

Step 2. Where the partition is newly created or intentionally recreated, format it with “format V: /FS:FAT32” before returning to Fix 3.

Fix 5. Repair the MBR and Boot Sector on Legacy BIOS Systems

Repairing the MBR restores legacy boot records when startup fails on older BIOS-based Windows installations. Microsoft recommends converting MBR disks to GPT before upgrading systems from BIOS to UEFI firmware. If you use Legacy BIOS, see the steps below.

Step 1. On an MBR disk, enter “bootrec /fixmbr” > Type “bootrec /fixboot,” which writes a new boot sector to the system partition.

Step 2. Set the System Reserved partition active if it is not already, using “select volume” > “active” inside DiskPart.

Fix 6. Run CHKDSK if the Windows Drive Has File System Errors

Bad sectors prevent boot file repairs during 0xc0000034 Windows 10 because written entries become unreadable afterward. CHKDSK marks damaged sectors and repairs directory structures, helping Windows avoid faulty storage locations afterward. Run CHKDSK after recovering important files because Part 4 explains why this order protects failing drives. Here is how to run CHKDSK:

Instructions. Enter “chkdsk D: /f” in your Windows command prompt. Leave it running to completion.

Fix 7. Use System Restore

A restore point reverses system changes before failure while keeping personal documents completely unaffected. Follow these steps to use System Restore.

Step 1. Head to “Troubleshoot” “Advanced options” “System Restore.”

Step 2. Pick a point dated before the failure > Press “Next” to perform it.

Fix 8. Reset or Reinstall Windows 10

Reset reinstalls Windows while preserving personal files and rebuilding essential boot components automatically. A clean installation rewrites partitions after reset fails, removing installed applications completely afterward. See the steps below to reset Windows:

Instructions. Choose “Troubleshoot” “Reset this PC” > Pick “Keep my files” rather than removing everything.

Part 3. Fix BCD Command Failures

During 0xc0000034 repairs, boot commands may return additional errors requiring different troubleshooting solutions. Each message identifies a specific problem and points toward the correct repair method.

Bootrec Does Not Find a Windows Installation

Zero identified Windows installations usually means Bootrec cannot read the Windows partition, not that it disappeared. Use “list volume” in DiskPart, then run “dir D:\Windows” to confirm the Windows folder exists. When the folder exists but Bootrec still fails, continue with Fix 3 using BCDBoot instead.

Bootrec/Fixboot Shows Access Is Denied

Access is denied commonly appears during error code 0xc0000034 repairs on GPT-based Windows installations unexpectedly. GPT systems use EFI partitions, and permission or partition issues often prevent the Fixboot command from succeeding. Determine your disk style using the DiskPart method explained earlier in Fix 5 carefully. Otherwise, assign the System Reserved partition a letter before rerunning the command successfully.

BCDBoot Fails to Copy Boot Files

Incorrect drive letters or unwritable target partitions usually prevent BCDBoot from copying boot files successfully. Verify both partitions using list volume, because recovery often assigns different drive letters automatically. Retry “bcdboot C:\Windows /s S: /f UEFI” after confirming the correct Windows and EFI drive letters, then follow Fix 4 if necessary.

The EFI or System Reserved Partition Is Missing or Not Assigned

A missing EFI or System Reserved partition requires creating a replacement before rebuilding Windows boot files successfully. Create a new partition in DiskPart, then format it using FAT32 for UEFI or NTFS. Assign the partition a drive letter before running Fix 3 to rebuild boot files. Otherwise, continue to Part 4 if creating partitions feels too advanced or risky.

The Windows Drive Letter Changes in Recovery Mode

Recovery often assigns different drive letters, making Windows partitions appear under another letter instead. Run “list volume” first, then verify the Windows folder using “dir D:\Windows” before repairs. Changing drive letters between recovery sessions remains completely normal and indicates no underlying problem.

Part 4. Recover Important Data Before Resetting or Reinstalling Windows

Earlier fixes for BCD error code 0xc0000034 leave personal documents completely untouched safely. Back up important files before resetting Windows or performing a clean installation.

When File Recovery Should Come Before Further Repairs

Move your data first if the repair commands keep returning errors, if CHKDSK flags bad sectors, or if the drive was cloned or resized recently. Each of those points to the disk itself being part of the problem. Sequencing is the stronger reason to act now. Once a reset begins writing, anything it does not preserve is overwritten, and no software reaches those files afterward.

Recover Files from an Unbootable Computer with Recoverit

When Windows 10 error code 0xc0000034 prevents startup, your personal files usually remain safely stored. Windows cannot boot, making normal file access impossible before repairs that reset or reinstall the system.

Recoverit helps protect those files before destructive repairs begin. Create a bootable USB on another computer, start the affected PC, then scan and recover important files without loading Windows.

Key Features

Crash Disk Access: Access files directly from crashed Windows drives without repairing startup problems first.

Deep Drive Scanning: Scans inaccessible system drives to locate recoverable files after severe boot failures.

Progressive Result Listing: Files appear as they are located, letting you copy the important ones before the scan ends.

Important Note: This tool retrieves data and rebuilds nothing. It has no effect on 0xc0000034, the BCD store, or the partitions holding them.

How to Recover Files Before Resetting Windows

To recover important files before resetting Windows, use the steps below with Recoverit System Crash Recovery:

Step 1. Prepare the Rescue Drive

First, choose “Other Tools” > Find “System Crashed Computer” > Click “Start.”

Step 2. Start the Failed PC with a Bootable USB

Insert a USB drive > Select it > Click “Create” > Connect the bootable USB to the affected PC > Set USB as the first boot device in BIOS.

Step 3. Save the Files to Separate Storage

After the PC starts, choose “Data Recovery” or “Hard Disk Copy.” Scan the drive > Select files > Save the files to an external location.

Part 5. Last Options and Prevention

With the BCD error code 0xc0000034 data safely recovered, the remaining repair options risk nothing irreplaceable:

Run CHKDSK Only After Important Files Are Safe

CHKDSK can now run freely, since a failure partway through threatens nothing you needed. Repeat the command from Fix 6, let it finish, then attempt the boot repairs again. A scan reporting unrecoverable sectors means the disk is failing. Replace it rather than rebuilding onto hardware that will fail again.

Use System Restore if Available

Retry System Restore with an older point than the one you tried before. Restore points are created automatically before updates and driver installations, so an earlier snapshot often predates whatever damaged the store. Each attempt can itself be undone, so trying more than once is safe.

Reset Windows and Choose Keep My Files First

Keep My Files remains the right choice even with a backup, since it preserves your profile and saves rebuilding it. Bear in mind that Microsoft has ended support for Windows 10 in October 2025, which makes a move to Windows 11 worth considering at this point.

Conclusion

Windows 10 error code 0xc0000034 indicates that the Boot Configuration Data (BCD) store is missing or damaged, preventing Windows from locating the information required to start. In many cases, rebuilding the BCD with Bootrec or recreating boot files using BCDBoot in the Windows Recovery Environment resolves the issue. Before resetting or reinstalling Windows, recover important files with Recoverit to prevent permanent data loss.