Repair HyperV Machine Boot (VHDX)

Your issue is extremely easy to fix. Simply create a new virtual machine in Hyper-V, selecting Use an existing virtual hard disk in New Virtual Machine Wizard:



Browse to and select your Enterprise LTSC 2019 vhdx file.

That's it.

EDIT 11-APR-2020

The above only works with Generation 1 VM and an MBR virtual hard disk. Because it has no System Reserved partition, the Windows partition C; must be set active.

If the virtual hard disk is GPT formatted from Generation 2 VM, EFI partition must be created before it can be used on a new VM.

When creating the new VM, be sure to select same VM generation than what the original VM was. A Generation 1 VM uses MBR formatted virtual hard disks, and Generation 2 VM GPT VHDs. A GPT VHD / VHDX does not work on Generation 1 VM, and an MBR VHD / VHDX does not work on Generation 2 VM.

Kari

You are now doing something wrong. The solution I told to you works 100% every time.

You do not need any boot partitions, when you create a new virtual machine using your existing VHD or VHDX file.

Best luck.

Kari

muchomurka said:

You need some software which
- can create bootable rescue cd/flash and
- can undelete gpt partition.
Unfortunately, I have no idea which program to use.

No, OP does not need any additional software. If the issue is that other partitions except Windows partition have been deleted from a functioning Windows VHD or VHDX file, the only thing required is to create a new VM using that VHD or VHDX file.

Kari

muchomurka said:

Documented functioonality somewhere? Link please.

Logical thinking is enough here. Try it, if it's not too difficult for you: If Windows partition is functioning on any VHD or VHDX file, it can always be used as existing VHD on a new VM.

Kari

muchomurka said:

So no evidence. Thanks.

So not capable to think. OK.