Hyperv enhanced session and RDP

I have a windows 10 computer and it has a hyperv windows 10 VM within it. When I try to log into the VM using enhanced session mode of HyperV, which requires RDP support, my logon is refused with the classic 'you need the right to sign in...".

I have verified the following:

The account I am using to logon is an administrator account and also has the User right 'allow logon on through terminal services'

Remote desktop connection is enabled through control panel system.

Firewall port for RDP is open and allows anyone in.

Is there something I have missed?

Thanks

David Z