This blog will shows you how to log exceptions that will occur in your ASP.NET web site in the Windows Event Log.
Eventlog Example
<%@ Page %>
<script language="vb" runat="server">
Sub Page_Load(sender As Object, e As EventArgs)
Dim a as Integer=0
Dim myEventLog as System.Diagnostics.EventLog
Try
a=1/a
Catch ex as Exception
myEventLog=new System.Diagnostics.EventLog()
myEventLog.Log="Application"
myEventLog.Source="asp"
myEventLog.WriteEntry(ex.ToString())
End Try
End Sub
</script>
<html>
<body>
<form id="form1" method="post" runat="server">
</form>
</body>
</html>
Hope this will help you.