Trying to send e-mail using button

Im using the following the code to try and send an e-mail
Imports System.Net.Mail
Imports System.Net.Mail.SmtpClient
Public Class _Default
Inherits System.Web.UI.Page
Protected Shared Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim myMail = CreateObject("CDO.Message")
myMail.Subject = "Test Email"
myMail.From = "a@b.com"
myMail.To = "c@d.com"
myMail.BCC = "e@f.com.com"
myMail.TextBody = "Test"
myMail.Send()
End Sub
End Class
 
but I get the following exception
"The SendUsing configuration value is invalid"
Anyone have any ideas?
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