This could be due to CredSSP encryption oracle remediation.
For more information, see https://go.microsoft.com/fwlink/?linkid=866660
To discuss further regarding this update please see: General Discussion - Unable to RDP: CredSSP
If the below steps do you help you in resolving your issue
please open a new forum post to Azure Virtual Machines
Resolution:
Open command prompt run as administrator and paste the below
command:
REG ADD
HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters\
/v AllowEncryptionOracle /t REG_DWORD /d 2
