下面这一段代码，用公司自己的邮箱发送，可以成功发送。但请问如何用163免费邮发送，我已经开通smtp服务了。

\'------------发送邮件开始
          Dim client As New System.Net.Mail.SmtpClient()
            client.Host ="smtp.ym.163.com"  
            client.Credentials = New System.Net.NetworkCredential(用户名),(密码))  \'   

            client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network
            Dim message As New System.Net.Mail.MailMessage()
            message.From = new System.Net.Mail.MailAddress("邮箱名称") 

           message.To.add("dtcq@163.com")
                  \'以下为项目进度发送内容
            message.Subject =“”“进度”

            message.BodyEncoding = System.Text.Encoding.UTF8
             Dim content As String
            content &= "本项目 进度:" & vbcrlf
             message.Body = content
            Try
                client.Send(message)
               messagebox.show("发送成功","邮件")
            Catch ex As Exception
                messagebox.show("发送失败:" & ex.message ,"邮件")
            End Try
\'------------发送邮件结束