Hey,
If you are trying to run Hyper-V on a VM on top of hypervisor or cloud, you need to enable nested virtualization on the hypervisor or use specific instances in the cloud. Couple examples:
https://www.server-world.info/en/note?os=ESXi_7&p=vm&f=4
https://www.starwindsoftware.com/blog/nested-virtualization-in-azure-with-starwind-vsan
Cheers,
Alex Bykovskyi
StarWind Software
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