emailing from a site.

[viper5646]

Hi all
I'm designing my first website using VS pro.
On my contacts form I have a Name, Email, Subject and Message Textbox.
I'm tryng to send an email using the data in the textboxes.
I keep on getting the following error: Command not implemented. The server response was: Command not implemented
I belive that Im missing the smtp port for Yahoo.mail which I don't know how to set up port 465.
This is the code I have behind the sent button.

Protected Sub btnsend_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnsend.Click
        Dim mail_to As String = "delta5646@yahoo.com"
        Dim mailmessage As System.Net.Mail.MailMessage = New System.Net.Mail.MailMessage()
        mailmessage.From = New System.Net.Mail.MailAddress(txtemail.Text.Trim())
        mailmessage.To.Add(New System.Net.Mail.MailAddress(mail_to.Trim()))
        mailmessage.Subject = txtsubject.Text.Trim()
        mailmessage.Body = txtmessage.Text.Trim()
        Dim smtpClient As System.Net.Mail.SmtpClient = New System.Net.Mail.SmtpClient()
        smtpClient.EnableSsl = True
        smtpClient.Send(mailmessage)
    End Sub

I also made these additions on the web.config

<system.net>
		<mailSettings>
			<smtp>
				<network host="smtp.mail.yahoo.com"/>
			</smtp>
		</mailSettings>
	</system.net>

Thank you