Hello, Our 802.1x Radius service has run uninterrupted for almost 2 years. Sometime in the morning yesterday, the server started rejecting authentications and Radius log shows loads of Certificate Compatibility problems as below. The certificate has not expired and the configuration on the server has not been amended for almost 2 years. I wonder why the server should suddenly start to reject user authentication on the basis of certificate compatibility. WARNING: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! WARNING: !! EAP session for state 0x2e8b52f829824b0d did not finish! WARNING: !! Please read http://wiki.freeradius.org/Certificate_Compatibility WARNING: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Ready to process requests. rad_recv: Access-Request packet from host 193.62.48.38 port 1814, id=197, length=248 Best Regards Clement Ogedengbe