This article will show you how to disable IPV6 in Windows Server 2008
It is not possible to remove IPV6 from a Windows Server 2008 environment, but it can be disabled quickly and with little effort. First, log in to the server and navigate to your Network Connections folder. Once there obtain the properties on all of your connections and adapters and clear the check box next to the Internet Protocol version 6 (TCP/IPv6) component.
This method disables IPv6 on your LAN interfaces and connections, but does not disable IPv6 on tunnel interfaces or the IPv6 loopback interface. In order to achieve this, add the following registry value (DWORD type) set to 0xFFFFFFFF:
HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services/Tcpip6/Parameters/DisabledComponents
This method disables IPv6 on all your LAN interfaces, connections, and tunnel interfaces but does not disable the IPv6 loopback interface. You must restart the computer for this registry value to take effect.