Files with the .VHDX extension contain disc image data – they are an extended version of VHD files. The additional functionality encompasses, inter alia, mechanisms to prevent data corruption, a larger maximum disc space – 64 TB instead of 16, improved virtualization efficiency on discs with large sectors, as well as adjusting said discs to the ballast.

The files are supported by Microsoft Windows 8 and Windows Server 8 – the loading of virtual machines using VHDX disc images is enabled by the Microsoft Hyper-V technology.