What does HRESULT 0x80310051 (FVE_E_RAW_BLOCKED) mean?

FVE_E_RAW_BLOCKED

Read this as a state-machine result

FVE_E_RAW_BLOCKED is a BitLocker facility HRESULT, not a Win32 filesystem error wrapped by an application. In this case BitLocker cannot enter raw-access mode because the volume is still mounted, open or otherwise in active use.

The BitLocker provider tracks encryption conversion, protection, lock state, metadata version, filesystem geometry and outstanding volume use independently. Two volumes can both appear “encrypted” in a UI while being in very different states for a management API.

What the code does not prove

The closest misleading interpretation is FVE_E_RAW_ACCESS, which means raw mode is already active rather than blocked before entry. Verify the returning method and state transition before assigning the incident to disk corruption, TPM failure or bad credentials.

Inspect the target, not just the message

1. Record open handles, mount points, filesystem state, cluster role ownership, VSS activity and the exact process requesting raw access.

Conversion status and protection status answer different questions: sectors can be encrypted while protectors are suspended, and a fully decrypted volume can still contain stale management context in a caller.

manage-bde -status
powershell -NoProfile -Command "Get-BitLockerVolume | Format-List *"

State checks specific to FVE_E_RAW_BLOCKED

References

• Microsoft: BitLocker operations guide
• Microsoft: manage-bde status
• Microsoft: GetConversionStatus method
• Microsoft: GetLockStatus method