i am developing a server-client program in which server will be showing datas sent by client across a network. without Authentication it works fine but once i give authentication i am not able to get datas from client.client is a winfrom application.i know that client must be given authorization to put data into server.can anyone tell me how to do that?i am developing based on the link given below

blog.bobcravens.com/2009/11/browse-files-on-remote-computers

posting server side authentication code
Code:
<authentication mode="Forms">
  <forms loginUrl="Login.aspx" name=".ASPXFORMSAUTH">


  </forms>
</authentication>

<authorization>
  <deny users = "?"/>
</authorization>

login.aspx
Code:
<script runat="server">
    Sub Login_Click(ByVal sender As Object, ByVal e As EventArgs)
        If ((UserEmail.Text = "[email protected]") And _
            (UserPass.Text = "000")) Then
            FormsAuthentication.RedirectFromLoginPage _
                 (UserEmail.Text, Persist.Checked)
        Else
            Msg.Text = "Invalid credentials. Please try again."
        End If
    End Sub
</script>
i have written validation code also.everything works fine on the server side but not able to get data from client side..

client program is written in c#,client-server communication is via http post.

code below is how client register with the server.
Code:
private void Register()
                {
                        // Register with the server.
                
                        
                        RegisterMessage registerMessage = new RegisterMessage
                        {
                                
                
                                ComputerName = Environment.MachineName,
                                TimeStamp = DateTime.Now,
                                UserInfo = Environment.UserDomainName + "\\" + Environment.UserName
                        };
                        PostMessage(registerMessage);
                }


private void PostMessage(BaseMessage message)
                {
                        BaseMessage[] messages = null;
                        try
                        {
                                messages = _webService.Poll(message);
                        }
                        catch (Exception ex)
                        {
                                // Service must be down.
                                //
                                MessageBox.Show(ex.ToString());
                                _pollMode = PollModeOptions.Register;
                        }

request to server is done based on the link below.