Solved
RADIUS Authentication using Microsoft W2K8 NPS
After reading several of the forum post on both Fortinet and Microsoft, I still am not able to get RADIUS authentication from an FLG100B (analyzer) and MS Windows Server 2008 SP2 (not R2). I think I am missing the required fields necessary to validate the admin authentication. *Each device and ping one another *Firewall on the server is disabled *NPS is working for VPN and Dialup access *RADIUS key is eight characters long (attempted with and without special characters) * The default " Use Windows authentication for all users" is present and valid *Referenced http://docs.fortinet.com/fgt/handbook/fortigate-authentication-40-mr2.pdf 

