session_end() of global.aspx does not execute on session.abandon() in vb.net code behind

hello everybody,

friends i am working on an application where i have to reset a flag in databse by a sql query whenever the session of a user is destroyed due to timeout or proper logout, so i used session.abandon() command in vb.net code behind and write the following code in session_en() function of global.aspx .


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 Sub Session_End(ByVal sender As Object, ByVal e As EventArgs)

        Dim connLogin As SqlConnection = New SqlConnection
        connLogin = New SqlConnection(ConfigurationSettings.AppSettings("ConnectionString"))
        If connLogin.State = ConnectionState.Closed Then
            connLogin.Open()
            Dim x = 17 'Session("IID")
            Dim cmdUpdate As SqlCommand = New SqlCommand("update status set Flag='1' where IID='" & x & "'", connLogin)
            cmdUpdate.ExecuteNonQuery()
            connLogin.Close()
            Context.Response.Write("database restored")
        Else
            Context.Response.Write("database cant be restored")
        End If

End Sub
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but any part of this function is not executed at all whenever session expires.

i have also given the session timeout value to 2 minutes in web.config file.

please help that exactly when and how this function can be executed as i need it at many more places.

thanks in advance.