VHDX was introduced in Windows 8/Windows Server 2012 to add features and flexibility missing in VHD that had become apparent over time.
[2] A Virtual Hard Disk allows multiple operating systems to reside on a single host machine.
The ability to directly modify a virtual machine's hard disk from a host server supports many applications, including: VHDX was added in Hyper-V in Windows Server 2012 to add larger storage capacity, data corruption protection, and optimizations to prevent performance degradation on large-sector physical disks.
Windows 7 Enterprise and Ultimate editions support this ability, both with and without a host operating system present.
The VHD format has a built-in limitation of just under 2 TiB (2048 GiB) for the size of any dynamic or differencing VHDs.
Later however, Microsoft used the VHD format[10] in Hyper-V, the hypervisor-based virtualization technology of Windows Server 2008.
[11] The Vista (or later) drive manager GUI supports a subset of the functions in the diskpart command line tool.
In 2017 Red Gate Software and Windocks introduced VHD based support for SQL Server database cloning.
This provides administrators with granular access to VHDs and the ability to perform some management tasks offline.
[22] Under Hyper-V, VFD files are usable through the VM settings for Generation 1 virtual machines.