What does HRESULT 0xC03A0004 (ERROR_VHD_FORMAT_UNKNOWN) mean?

Status / error code:

Category:

Constant name:

Source:

Facility:

Operating System:

Description:

The system does not recognize the file format of this virtual hard disk.

Could be also:
Constant	Type	OS
STATUS_VHD_FORMAT_UNKNOWN	NTSTATUS	Windows

Previous	Next
ERROR_VHD_DRIVE_FOOTER_CORRUPT	ERROR_VHD_FORMAT_UNSUPPORTED_VERSION

ERROR_VHD_FORMAT_UNKNOWN

ERROR_VHD_FORMAT_UNKNOWN means Windows does not recognize the file as a supported virtual hard disk format. A .vhd or .vhdx extension alone does not prove that the file contains a valid virtual disk.

What to check

Verify that the file was copied completely and is not an ISO, raw image, archive, placeholder, or partially restored object with a renamed extension.
Try Get-VHD on a supported Hyper-V host to identify the actual format and metadata.
Do not convert a file until its source format is known; conversion tools cannot repair arbitrary or truncated input.

Get-VHD -Path "D:\VMs\disk.vhdx"

Microsoft: Get-VHD

Microsoft: Manage virtual hard disks

Microsoft: VHDX file format specification

Looking for a different code? Search another status or error code.