This could be due to CredSSP encryption oracle remediation - RDP to Windows 10 pro host

Error

 Following Windows security updates in May 2018, when attempting to RDP to a Windows 10 Pro workstation the following error message is displayed after successfully entering user credentials:

An authentication error occurred. The function requested is not supported.

This could be due to CredSSP encryption oracle remediation

Screenshot

Solution

File rd_patch.reg:

Windows Registry Editor Version 5.00

 

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP]

 

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters]

"AllowEncryptionOracle"=dword:00000002

 

For those who would like something easy to copy / paste into an elevated command prompt:

reg add HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters /v AllowEncryptionOracle /t REG_DWORD /d 2 /f