trying to get this script to work

Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp" -Name "UserAuthentication" -Value 3
([ADSI] "WinNT://localhost/Administrators").remove('WinNT://localsetup')
([ADSI] "WinNT://localhost/Administrators").add('WinNT://mydomain.com/tjackson')
{enable-psremoting -force}

I am trying to get all this to run at the same time. any ideas?