How to Convert Hyper-V VHD-files to VHDX

Using PowerShell to Convert VHD to VHDX

Open a PowerShell window on the server that houses your .vhdx files and execute the following command:

Convert-VHD –Path c:\test\win7.vhdx –DestinationPath c:\test\win7.vhd

You can also specify whether you want a dynamic or fixed disk – but that is optional. To make the virtual hard disk type dynamic, use the switch -VHDType Dynamic. To make the virtual hard disk type fixed, use the switch -VHDType Fixed.

You can actually use the same procedure to convert a VHD file back to a VHDX file:

Convert-VHD –Path c:\test\win7.vhd –DestinationPath c:\test\win7.vhdx

We will figure out whether you want the new file to be a VHD / VHDX depending on the file extension that you provide. You can also specify whether you want a dynamic or fixed disk but that is optional.