You must to create a GPO to modify (or create if not exist) HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\tcpip6\Parameters\DisabledComponents. If you don't see DisabledComponents, create it by adding the following registry value (DWORD type) with this values:
1 to disable tunnel interfaces
2 to disable 6to4
3 to disable ISATAP
8 to disable Teredo
16 to disable LAN and PPP interfaces
32 to Set preference of IPv4 over IPv6
255 to disable IPv6 completely
1 to disable tunnel interfaces
2 to disable 6to4
3 to disable ISATAP
8 to disable Teredo
16 to disable LAN and PPP interfaces
32 to Set preference of IPv4 over IPv6
255 to disable IPv6 completely
This link may help you to create your GPO: http://www.unidesk.com/blog/gpos-set-custom-registry-entries-virtual-desktops-disabling-machine-password