I've read theory that Windows 7 SP1 can be installed on a Hyper-V Gen 2 VM because SP1 brought UEFI support; however, I've yet to see a thread where someone has got this working. Here are the basic steps I have taken: Install Windows 7 SP1 on gen 2 VM with Secure Boot enabled. Hyper-V Error: "The image's hash and certificate are not allowed." Install Windows 7 SP1 on gen 2 VM with Secure Boot disabled. Freeze at Starting Windows screen. Install Windows 7 SP1 on gen 1 VM. Fully update Win 7. Install Hyper-V Integration Components. On Gen 1 VM, boot into WinPE. Run MBR2GPT to convert the .vhdx to GPT format. Create new gen 2 VM, select old gen 1 Win 7 .vhdx as gen 2 VM's disk. With Secure Boot enabled: Hyper-V Error: "The image's hash and certificate are not allowed." With Secure Boot disabled: Freeze at Starting Windows screen. I've read that the freeze is due to driver support for the SCSI device that gen 2 uses. Does anyone know what driver I would need?
If the HyperV Gen2 VM provides a pure UEFI with no CSM module/feature, then there is no way to run Windows 7 there. Windows 7 does not support GOP and still relies on legacy BIOS INT10 emulation provided by the CSM. Please note that Windows 7 does not support Secure Boot at all and never will.