Here, as promised, is the slide deck for my presentation at SpiceWorld 2019 this morning, about Native boot VHDs in Windows 10. Click this download link for the PowerPoint file (OneDrive).
Native Boot VHDs in Windows 10: Using GPT and Type-2 HyperVisor VHDs (.vhdx)
For GPT, add the “convert GPT” command to the DISKPART script, as follows:
create vdisk file=F:\W10PRO.vhdx maximum=51200 type=expandable
create part primary
When creating a VHD file for native boot, always use MBR partitioning! To upgrade Windows on a native boot VHD, you must temporarily run it as a virtual machine. This means attaching that VHD to a VM.
An MBR partitioned VHD is easy to attach to a VM: mark its Windows partition active. OTOH, a GPT partitioned VHD with only a single partition for Windows requires that you manually create system partitions before it’s usable as a bootable VM (MSR and EFI along with the system partition at a minimum, recovery partition if a complete emulation of “normal Windows 10” is desired).
Say you want to use a GPT partitioned VHD for native boot for some reason (and we can’t think of a valid one). In that case, it is best to first create a Generation 2 VM in Hyper-V, then install Windows 10 on it. This takes care of the partitioning automatically, and does so correctly. That VHD can then be added to the boot menu for native boot, or used as a VM.