I'm using a domain laptop to remotely manage a bunch of Hyper-V Server 2016, also joined to this domain. But since a recent domain change, I came across an issue with one server.
I can open Hyper-V manager, add the faulty server and get the list of VMs. Even the preview of the VM screen is showing when it's running.
But whenever I try connecting to a VM, I get the error with CredSSP stating (approximative translation from French, see exact error message here):
"An authentication error occured, requested function cannot be provided" blablabla.
I already tried to add the registry key on the Hyper-V Server:
reg add HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters /f /v AllowEncryptionOracle /t REG_DWORD /d 2
But it's still not working.
Since I'm in a domain, I looked at the GPO, but the "Encryption Oracle Remediation" does not show in the GPO manager.
Strange thing, I can connect and manage VMs without any problem on another server also running Hyper-V Server 2016 (those 2 servers are in a different subnet).
The VMs are running Ubuntu Server 20.04 if it matters.
Any idea on how to fix this please?
EDIT: both servers are up to date.
I figured out the issue. It wasn't related to the Hyper-V Servers, but to the old Windows 10 laptop I use to manage the servers.
I added the key in the registry:
reg add HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters /f /v AllowEncryptionOracle /t REG_DWORD /d 2
and it worked like a charm.
Sorry for disturbing...