This is a supported scenario: Supported operating systems in Virtual Server 2005 R2 Virtual Server 2005 is not free to download, you can find the link below: Microsoft Virtual Server 2005 R2 SP1 - Enterprise Edition Thanks for your understanding and please let me know what I can help. Unfortunately, Windows Server Hyper-V doesn’t support Windows NT 4.0 as the guest OS, as the following article shows: About Virtual Machines and Guest Operating Systems If the Windows NT 4.0 virtual machine has Service Pack 6a patched, you can consider to use Virtual Server 2005 R2 SP1 to host it. Personally I would see if there was a way to upgrade the server, but if you're beyond that, I would try to capture an image of the server by using a software like Symantec Ghost from within the VMWare VM and unpack the captured ghost image inside a Hyper-V VM. According to this article, P2V is not supported by SCVMM on OS's such as NT4: Most other P2V / V2V conversion tools (SCVMM, Disk2VHD, etc.) will most likely not be able to convert NT4, due to its lack of VSS.
