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Registry: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Virtual Machine\Guest\Parameters

In a Hyper-V guest, the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Virtual Machine\Guest\Parameters has some information about its host.

Determine the hostname on which a Hyper-V (?) guest is running:

(get-itemProperty 'HKLM:\SOFTWARE\Microsoft\Virtual Machine\Guest\Parameters').hostname