Hi,
Your question is a little confusing. Are you trying to set up a VPN connection? Network Access Protection (NAP) is not required for this, although you can use NAP with VPN. What do you mean about showing "off" in DHCP?
If you want to use NAP with VPN enforcement you can try testing this using instructions in the NAP VPN step by step guide: http://www.microsoft.com/downloads/details.aspx?FamilyID=729bba00-55ad-4199-b441-378cc3d900a7&displaylang=en
-Greg
