Network Address Translation (NAT) is currently installed as a routing protocol, and must be removed before enabling Internet ...

Network Address Translation (NAT) is currently installed as a routing protocol, and must be removed before enabling Internet Connection Sharing and/or Windows Firewall. To remove Network Address Translation, open the Routing and Remote Access Manager snapin and expand the router's entry in the left pane. Delete the Network Address Translation routing protocol from the list of IP routing protocols.