VMware 6.0 (Free version) VSphere CLI

Hi

I'm trying to follow the VMware hardening guide for my ESXI version.  For some of the recommendations it requires you to use the VSphere CLI.

Here’s What I'm doing:

Run VSphere CLI as administrator
Connect-VIServer
Enter IP and credentials

At this point if I do a "get-vm" then a list of all the vm's is displayed

However if I try any of these:
Get-VM | New-AdvancedSetting -Name "isolation.device.connectable.disable" -value $true
Get-VM | New-AdvancedSetting -Name "RemoteDisplay.vnc.enabled" -value $false
Get-VM | New-AdvancedSetting -Name "tools.setInfo.sizeLimit" -value 1048576
Get-VM | New-AdvancedSetting -Name "isolation.tools.vixMessage.disable" -value $true
etc.....
All of which are from the official hardening guide.

I get "Current license or ESXi version prohibits execution of the requested operation."

Does any one know why?  Seems odd you cant harden the free edition, or is it I'm doing something wrong?

Thanks