To resolve this error, verify RADIUS server settings. To perform this procedure, you must be a member of the Domain Admins ...

To resolve this error, verify RADIUS server settings. To perform this procedure, you must be a member of the Domain Admins group.

To configure RADIUS server settings:

. Contact the RADIUS server vendor for configuration assitance. Vendors might provide updates that allow the RADIUS server to send response messages that comply with the RADIUS protocol. 
2. If  the vendor cannot provide instructions or updates that allow the RADIUS server to send RADIUS protocol-compliant messages, you must use a RADIUS protocol-compliant server with NPS.