Dear all Thank you for the responses I am using openssl tool for certificate generation.I have inclided the file xpextensions while generating certificates.The same certificates worked well with Navis radius server and windows xp as client.So this may not be the problem here Anoop hi, how did you generate your certificates? alan They also say this: \"The most common problem with PEAP is that the client sends a series of Access-Request messages, the server sends an series of Access-Challenge responses, and then... nothing happens. After a little wait, it all starts again. If you see this happening STOP! The RAIDUS server certificate has to have special OID\'s in it, or else the Microsoft clients will silently fail. etc.\" There we messages yesterday on this list describing this exact problem, and how to fix it. The file \"eap.conf\" describes this problem and how to fix it. The FAQ says what to do when PEAP or EAP-TLS doesn\'t work with a Windows client. Regards Anoop