The default Permission settings are read only and cannot be changed, unless a group policy is set to override this. Use the ...

The default Permission settings are read only and cannot be changed, unless a group policy is set to override this.  Use the "Remote Desktop Users" group to grant user rights to log on remotely. The Administrator group has full access to all connections.  To enable Administrator rights to customize permissions, open "Do not allow local administrators to customize permissions" in the group policy snap-in under:  Computer Configuration->Administrative Templates->Windows Components->Terminal Services->Terminal Server->Security.