Nagios email notification issue

Hi all,

i had installed nsclient in my windows 2003 server. nagios will sent out notification email to me, however the email notification alert is not tally with the real issue. In Nagios it was showing critical windows alert for authentication(monitoring from event log). However when i received email sent by nagios, the alert message is not authentication alert. It was ping alert. And it only send ping alert for all the critical issue(like authenticate, transaction errors).

Please advise where goes wrong. Thanks.