STATUS_FVE_NOT_OS_VOLUME (0XC0210012) – Not Boot Volume Fix

1. You’re trying to encrypt a drive that isn't the boot OS volume

This is the most common reason for error 0xC0210012. BitLocker is picky – it only encrypts the boot drive (C:) by default when you run the standard "Turn on BitLocker" wizard. If you select any other drive, like D: or E:, you get this error if you're expecting it to act as a system drive.

What's actually happening here: BitLocker checks the volume's attributes. It looks for the SYSTEM or BOOT flag in the partition table. Your selected volume doesn't have them, so BitLocker refuses to proceed.

The fix: Use manage-bde on the correct drive

Open Command Prompt as Administrator. Run:

manage-bde -status

Look at the output. Find the drive letter with Used Space and Conversion Status. The boot volume is usually C:. If you're trying to encrypt C:, and it fails, skip to cause #2. If you're trying to encrypt a data drive, you're doing it wrong for this error.

To actually encrypt a non-OS data drive with BitLocker (which is allowed), use:

manage-bde -on D:

Replace D: with your data drive. This works because manage-bde doesn't require the drive to be the boot volume – it just encrypts the data. The error 0xC0210012 only shows up when you try to use the GUI wizard on a volume that isn't the boot drive.

The reason step 3 works: manage-bde is the low-level tool that doesn't enforce the OS volume check. The GUI wizard does. So if you need to encrypt a data drive, always use manage-bde.

2. Multiple system partitions or an EFI system partition being targeted

Sometimes you accidentally try to encrypt the EFI System Partition (ESP) or the System Reserved partition. These are small partitions (100–500 MB) that Windows creates during setup. They're not the boot OS volume – they hold boot files.

I've seen this happen when someone runs BitLocker from Disk Management and clicks on the wrong partition (like "System Reserved" or "EFI"). The error pops up because these partitions are marked as SYSTEM but are not the BOOT volume.

The fix: Identify and ignore system partitions

Open Disk Management (diskmgmt.msc). Look for partitions labeled "System Reserved" or "EFI System Partition." They have no drive letter by default. You can't encrypt them with BitLocker anyway – and you shouldn't.

If you already assigned a drive letter to the EFI partition (maybe by mistake), remove it:

diskpart
list volume
select volume X (where X is the EFI volume number)
remove letter=E (or whatever letter you assigned)
exit

After that, error 0xC0210012 won't appear because you won't be trying to touch that partition anymore.

3. The target volume is not marked as a boot drive in the BCD store

This is a rare case but happens if you cloned a Windows installation or messed with the Boot Configuration Data (BCD). The volume might be C: and contain Windows, but BitLocker checks the BCD entry to see if it's the current boot OS volume. If the BCD points to a different partition (like from a failed dual-boot or a clone), you get this error.

What's actually happening: BitLocker calls the FveGetVolumeInfo API, which reads the BCD. If the volume's GUID doesn't match the one in BCD for "Windows Boot Loader," it bails out.

The fix: Rebuild the BCD or assign the correct drive

This fix is for advanced users. Boot from Windows installation media and open Command Prompt (Shift+F10). Run:

bootrec /fixboot
bootrec /rebuildbcd

Follow the prompts. It will scan for Windows installations and add the correct entry. After a reboot, BitLocker sees C: as the correct boot volume.

If you cloned a drive and the original still exists, disconnect it. Having two volumes with the same OS can confuse BCD.

Summary Table