
With Windows 8 and Windows Server 8 Microsoft released a new file format for Virtual Hard Disk called VHDX.
The VHD format, which was availible since 2005 (Microsoft Virtual PC) and is now used by Microsoft Hyper-V and other Hypervisor, had some limitations.
The latest version of the VHD format was limited to 2TB of size and a block file size of 512bytes.
Now with VHDX Microsoft kills this limitations and brings some other improvements:
- Supports up to 16TB size
- Supports larger block file size
- improved performance
- improved corruption resistance
At this time you can use the VHDX format only with Windows 8 and Windows Server 8. But you can convert VHDs the VHDX format and VHDX disks back to VHDs.


how can we convert vhdx back to vhd format? Thank you in advance
With the Hyper-V Manager you can convert a VHD to VHDX and also a VHDX to VHD.
Or you can do it via Windows PowerShell and the Convert-VHD cmdlet.
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