Windows error 0xc000000f (often typed 0xc00000f): how to fix it

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Error 0xc000000f means the boot process could not load a file it needs, so the PC stops before Windows starts. Guides sometimes write it as 0xc00000f and describe the same boot problem. The usual fix is Startup Repair or rebuilding the boot configuration data (BCD) from Windows recovery media.

Applies to:WindowsPhysical PCs and Azure virtual machines, BIOS/MBR and UEFI
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What it means

The code 0xc000000f appears on a blue or black Recovery screen when the PC starts. Windows Boot Manager or the Windows loader could not load a file it needs, and because that happens before Windows loads, you never reach the desktop.

Some third-party guides write the code as 0xc00000f, with one zero fewer, and describe the same boot problem. Compare the digits on your own screen. The code Microsoft documents is 0xc000000f.

The screen names the file that failed, and that tells you which fix fits. Microsoft describes three variants: the Boot Configuration Data (\Boot\BCD) is missing or has errors, winload.exe could not be loaded, or a critical system driver (a .sys file) is missing or damaged.

One thing to know about the sources: Microsoft's article on this error is written for Windows virtual machines on Azure. I found no Microsoft page for physical PCs. The first steps below (unplug devices, Startup Repair, bootrec, chkdsk, BIOS check) follow a third-party reference, NeoSmart, plus general practice. The manual BCD and driver repairs are adapted from Microsoft's Azure article.

BitLocker warning: many Windows 10 and 11 PCs have an encrypted system drive. Before you change boot settings or run repair tools, make sure you can get the BitLocker recovery key (for example from the Microsoft account the PC was set up with). Without it you can be locked out of your own files.

Symptoms and causes

You are likely dealing with this problem if:

  • A blue or black Recovery screen appears at startup instead of Windows.
  • The status line reads something like File: \Boot\BCD Status: 0xc000000f.
  • The file named may instead be \Windows\system32\winload.exe or a driver such as \Windows\System32\drivers\<name>.sys.
  • Windows cannot boot.

The usual causes, most common first:

Corrupt or missing BCD
The boot configuration data is damaged or gone. NeoSmart lists disk write errors, power loss or abrupt shutdown during a boot-sector write, boot-sector viruses and manual BCD editing mistakes as triggers.
BCD points to the wrong partition
The DEVICE and OSDEVICE entries in the BCD are missing or refer to the wrong partition, so the boot manager cannot find Windows.
Missing or corrupt system file
A file other than the BCD or winload.exe, usually a driver .sys file, is missing or damaged on the Windows disk.
File system damage or bad sectors
Errors on the disk can corrupt boot files even when nothing was edited.
Cable or SATA mode problems
A loose or failing disk data cable, or a SATA mode (AHCI/IDE) mismatch in the BIOS, can produce the same error according to NeoSmart.

How to fix it

Work through these in order. They start with the quickest, safest checks and move to deeper repairs; stop as soon as the problem is gone.

1.Unplug extras and check the drive connection

Easy

A stray USB drive, disc or loose cable can make the PC fail to read the disk.

  1. Shut the PC down, unplug USB drives and card readers, and remove any discs.
  2. On a desktop, reseat the data cable of the internal drive at both ends. Then start the PC again.

2.Run Startup Repair from Windows install media

Easy

Startup Repair can fix a damaged BCD and other boot problems automatically.

  1. Boot from a Windows USB or DVD made with the official Microsoft media creation tool, on another PC if needed.
  2. Choose Repair your computer, then Troubleshoot, then Advanced options, then Startup Repair.
  3. Select your Windows installation and let it finish, then restart without the media.

3.Rebuild the BCD with bootrec

ModerateChanges settings

If Startup Repair fails, rebuilding the BCD from the recovery Command Prompt often restores the boot entry.

Before you start: This writes to the boot configuration. Confirm you have your BitLocker recovery key first, because boot changes can trigger a recovery-key prompt. Back up important data first if you can reach the disk from another PC. Do not run /fixmbr or /fixboot unless you need them, since they overwrite boot code.

  1. Boot from the install media, choose Repair your computer, then Troubleshoot, Advanced options, Command Prompt.
  2. If the Windows drive is BitLocker-protected and shows as locked, unlock it first. Replace C: with the real letter and the placeholder with your 48-digit recovery key.
    Command Prompt
    manage-bde -unlock C: -RecoveryPassword <recovery key>
  3. Rebuild the BCD.
    Command Prompt
    bootrec /rebuildbcd
  4. If asked to add the installation to the boot list, press Y. Then restart.

4.Check the disk for errors

ModerateChanges settings

File system damage or bad sectors can corrupt boot files, and repairing them may be needed before any other fix holds.

Before you start: Disk repair can modify files. Back up what you can first. If the drive is BitLocker-encrypted, have the recovery key ready, since the recovery Command Prompt may show the drive as locked until you unlock it with manage-bde -unlock. If chkdsk keeps finding errors, the drive may be failing, so check its SMART status and replace it if needed.

  1. Open the recovery Command Prompt as above. Letters can differ in recovery, so confirm which one holds Windows (for example with dir C:).
  2. If the drive is locked, unlock it with your recovery key (see the previous fix), then run chkdsk on the Windows drive, replacing C: with the real letter.
    Command Prompt
    chkdsk C: /f

5.Check the SATA mode in the BIOS

ModerateChanges settings

A changed SATA mode can stop the PC from reading the Windows disk.

Before you start: Write down the original value before changing anything so you can switch back. Changing BIOS settings can also trigger a BitLocker recovery-key prompt, so keep the key at hand.

  1. Enter the BIOS/UEFI setup (the key varies by maker, often F2 or Del).
  2. Check the SATA mode (AHCI or IDE). If it was changed recently, set it back to the previous value, then save and exit.

6.Repair the BCD device entries manually (disk attached to another PC)

AdvancedBack up first

Microsoft documents this repair for Azure VMs when the Device and OSDevice entries are missing or wrong. The device commands below can be adapted for a drive attached to another Windows machine. Microsoft's article also sets Azure-only options (recovery and boot status policy, integrity services). They are left out here because Microsoft supports them only for Azure VMs and they switch off automatic recovery on a normal PC.

Before you start: First image or copy the problem disk, or at least export its existing BCD so you can put it back: bcdedit /store <path to BCD> /export <backup file>. Wrong values can leave the PC unbootable. If the disk is BitLocker-encrypted, you need the recovery key and may have to unlock it with manage-bde -unlock <drive>: -RecoveryPassword <key> before the other PC can read it. On Azure, Microsoft prefers restoring the VM from a recent backup first.

  1. Attach the problem disk to another PC as a data disk. Open an elevated Command Prompt there.
  2. Identify the Boot partition (it has a hidden Boot folder, about 300 to 500 MB) and the Windows partition. Below, <Boot> and <Win> stand for their drive letters.
  3. Back up the existing BCD, then list the store and note the identifier of the Windows Boot Loader entry. For BIOS/MBR (Gen 1) use the first two commands, for UEFI (Gen 2) use the same commands with the \EFI\Microsoft\Boot\BCD path.
    Command Promptrun as administrator
    bcdedit /store <Boot>:\Boot\BCD /export <backup file>
bcdedit /store <Boot>:\Boot\BCD /enum /v
  4. Set the device entries, even if they already look right (Microsoft says to run them regardless). Replace {<id>} with the identifier you noted. For UEFI, use \EFI\Microsoft\Boot\BCD as the store path.
    Command Promptrun as administrator
    bcdedit /store <Boot>:\Boot\BCD /set {bootmgr} device partition=<Boot>:
bcdedit /store <Boot>:\Boot\BCD /set {<id>} device partition=<Win>:
bcdedit /store <Boot>:\Boot\BCD /set {<id>} osdevice partition=<Win>:
  5. Put the disk back in the original PC and start it.

7.Replace a missing or corrupt driver file

AdvancedBack up first

Use this when the Recovery screen names a .sys file under \Windows\System32\drivers. This follows Microsoft's documented steps.

Before you start: Back up the disk first. If the drive is BitLocker-encrypted, have the recovery key ready and unlock the drive with manage-bde -unlock if it shows as locked. Replacing system files by hand can leave Windows unbootable if you copy the wrong file.

  1. Attach the disk to another PC (or use the recovery Command Prompt). Run chkdsk on it first, replacing <drive> with its letter.
    Command Promptrun as administrator
    chkdsk <drive>: /F
  2. If that does not help, rename the bad file, for example <name>.sys to <name>.sys.old. If the rename is refused, take ownership with takeown first.
  3. Search the WinSxS folder for good copies of the file.
    Command Promptrun as administrator
    dir <name>.sys /s
  4. Copy the latest version to \Windows\System32\Drivers\. If it still fails, try the previous version.

Check that it worked

  • The PC starts past the Recovery screen and reaches the Windows sign-in screen.
  • After a restart, Windows boots again without showing 0xc000000f.

If it still fails

  • If chkdsk keeps reporting errors, check the drive's SMART status. The disk may be failing and should be backed up and replaced.
  • Copy your files off the drive (from another PC or a recovery environment) before you try reinstalling Windows.
  • If this is an Azure VM, restore from a recent backup or see Microsoft's article linked below, and contact Azure support if needed.

Questions

Is 0xc00000f the same as 0xc000000f?

Guides that use the short spelling describe the same boot problem. The code Microsoft documents is 0xc000000f, so check the digits on your Recovery screen and follow this article either way.

Sources

  1. Boot error code 0xC000000F in an Azure VMOfficial · Microsoft Learn
  2. 0xc000000f (NeoSmart Wiki) · NeoSmart Technologies

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