Allow logon through Terminal Services in Windows Server Operating Systems
Running a server operating system only Administrator is allowed for remote access.
You have to give this permission to Remote Desktop User Group as well - in according GPO setting.
Open Group Policy Editor (gpedit.msc) and move to:
Computer Configuration/ Windows Settings/ Security Settings/ Local Policies/ User Rights Assignment/
In the right pane you will find setting: "
"Allow log on through Remote Desktop Services"
-> Add "Remote Desktop Users"
