Microsoft has been using the same VHD format since the one created by Connectix in 1995. That was created to allow Windows 3.1 to run on Mac computers. It has been improved, but as with any other product's lifecycle, its life somewhat ended when Windows 2012 Hyper-V was introduced.

On Windows Server 2016, the default format is VHDX and VHDX provides lots of features and enhancements compared to its previous version. That is not to say that VHD files have gone away, you might be migrating from an older version of Hyper-V, for example Windows 2008 R2, or you might still be using VHD files because Microsoft Azure only supports VHD files and you want to maintain a level of mobility between your on-premises infrastructure and Microsoft Azure.

VHDX files were designed to work well with all the new modern storage options and VHDX files have the capability of providing reliability and store large scenarios. VHDX now supports 64 TB against 2 TB of VHD. Also, it supports...