This week it seems that the NPS server has decided to stop authenticating Wireless clients running windows 7.
I have been over a similar older thread here and after trying the suggestions there still had no luck
https://social.technet.microsoft.com/Forums/windowsserver/en-us/76644dcc-911d-451e-b7f1-39269db43ac7/nps-event-6273-reason-code-16?prof=required
NPS is setup to authenticate 802.11 wireless clients with PEAP
The NPS server as a cert based on RAS/ IAS template with subject and subject alternate names filled, the clients have valid client certs and trust the domain based CA.
The RADIUS client is working normally and the shared secret has been changed several times as in the previous post suggestions.
Any more ideas?