Unable to RDP - CredSSP Encryption Oracle Remediation
Quick fix:
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters]
"AllowEncryptionOracle"=dword:00000002
Or:
 gpedit.msc -> Computer Configuration -> Administrative Templates -> System -> Credentials Delegation -->
change the Encryption Oracle Remediation policy to Enabled, and Protection Level to Vulnerable
More info: https://blogs.technet.microsoft.com/mckittrick/unable-to-rdp-to-virtual-machine-credssp-encryption-oracle-remediation/