I came across an virtual machine in .ova format. OVA is an open standard for packaging and distributing virtual appliances. The .ova-package(file) is a tar-archive which can be decompressed and you will get two files: .ovf and .vmdk.

Information about the machine settings (vCPUs, Memory, NIC etc.) is stored in the .ovf file. The .ovf file is a .xml-file. You can launch the file in your favorite browser/xml-parser.

Now you need to create a machine manually with the specifications found in the .ovf. Virtual appliances are very picky on the specifications and might refuse to boot, crash, or get into problems later if the configuration is not exact (2 CPUs for example).

A Legacy Network Adapter may be needed for the system to recognize the NIC, in that case you need a Generation 1 virtual machine. I have also seen Dynamic Disks on a *nix system grow endlessly. Using a fixed disk corrected the problem. YMMW.


The diskimage(.vmdk) has to be converted into a native Hyper-V diskimage(.vhd/.vhdx).

I tried Microsoft Virtual Machine Converter but it failed and OVF Import/Export tool required an System Center VMM management server which i didn’t have.


It turned out that VirtualBox had tools to to convert the image successfully.

You can either download and install VirtualBox, or for a GUI version scroll further down and follow the instructions how to use “CloneVDI”.



Use VirtualBox command line utilities to convert the image.

Download and install VirtualBox from https://www.virtualbox.org/.


You can deselect the USB/NIC drivers and other options during the installation. They will not be needed for converting diskimages and you will get less clutter on your machine.




You don’t need to start VirtualBox.

VirtualBox has a commandline utility that will be used to convert the image.

VBoxManage clonemedium: (earlier versions used VBoxManage clonehd) This Commandline duplicates a virtual disk/DVD/floppy medium to a new medium (usually an image file).

VBoxManage clonemedium [disk|dvd|floppy]

[--format VDI|VMDK|VHD|RAW|]
[--variant Standard,Fixed,Split2G,Stream,ESX]

In this example, the source diskimage is named “infile.vmdk” and is located in the C:\HYPER-V directory. Output image will be of vhd-format and named “outfile.vhd”. The commandline is: "VBoxManage.exe clonemedium --format vhd infile.vmdk outfile.vhd"



Use CloneVDI to convert the image.


CloneVDI is the (VirtualBox) GUI-tool for cloning images, but it does not support all image formats that VirtualBox VBoxManage does (and vice versa).

Download CloneVDI from the following location: VirtualBoxFourm


The CloneVDI is a pretty straightforward utility.

If you get an error about an unsupported format, try VirtualBox commandline utils instead.