Export Hyper-V Virtual Machine in Windows 10  

Steve C said:

I experimented exporting a VM before uninstalling Hyper V. The export files just replicate the folder tree I had already designated in another location. On reinstalling Hyper V, the original VM was found in its original location and the VM worked OK.

Yeah, export is really just a backup option. It's also good for importing on another PC.

Bree said:

One big advantage of exporting a VM is the option to import using the VM's original unique ID. This is essential to preserve the Win10 activation, such as when moving an activated VM to another PC. Just deleting an activated Win10 VM when your done testing means you'll loose the chance to ever use that digital license again.

Like any physical machine, a VM's digital license is recorded on MS activation servers and linked the the hardware ID of the machine. Also, the disk is not part of that hardware ID. This means you should be able to preserve your digital license for reuse later by swapping out the VM's .vhdx, replacing it with and empty new one, then exporting the VM. When imported you'll have a VM with no OS but an existing digital license for W10, just like a physical machine with a replacement HDD.

Import Hyper-V Virtual Machine in Windows 10

Yep ‐ I have several activated VMs with no disk attached and they take up little space.

In fact, I recommend you do detach the vhdx file and then when you restore it on another device it does not look for a vhdx that does not exist. I have had issues where it refuses to restore properly if it cannot find the same vhdx file.

As as aside, you can have several vhdx files attached to same vm, and you can change boot order or even have a multiboot menu.

Of course, you get into the perennial discussion that that violates the EULA but frankly it is absurd to expect user to keep attaching and detaching virtual hard drives to comply with VM when you can only use one at a time anyway.