Question

This is web config

 <appSettings>
     <add key="SmtpServer" value="gmail.com"/>
     <add key="SmtpUtilisateur" value="[e-mail]"/>
     <add key="SmtpPassword" value="12345678"/> 
 </appSettings>

This my vb method

 Sub SendSimpleMail()


    Dim Message As New Mail.MailMessage
    Dim utilisateur As String
    Dim pass As String
    Dim server As String

    utilisateur = ConfigurationSettings.AppSettings("StmpUtilisateur")
    pass = ConfigurationSettings.AppSettings("SmtpPassword")
    server = ConfigurationSettings.AppSettings("SmtpServer")

    Message.From = "[e-mail]"
    Message.To = "[e-mail]"
    Message.Subject = "test"
    Message.Body = "salut je voulais savoir comment tu allais"


    Message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate", "1")
    Message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername", utilisateur)
    Message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtppassworld", pass)
    SmtpMail.SmtpServer = server
    Try
        SmtpMail.Send(Message)
    Catch ex As Exception
        Label1.Text = ex.Message
    End Try


End Sub

I get an error like the “transport fail in connection to server”

I don’t know why this is not work well…

Thank’s for helping me!

This in vb.net

Answer 1

First, it is recommended to use System.Net.Mail instead of SmtpMail, since the latter has been declared obsolete by Microsoft.

Second, the Gmail SMTP server requires a secure connection which can be set using SmtpClient.EnableSsl.

Your example could be changed to the following:

Sub SendSimpleMail()

    Dim utilisateur As String = ConfigurationSettings.AppSettings("StmpUtilisateur")
    Dim pass As String = ConfigurationSettings.AppSettings("SmtpPassword")
    Dim server As String = ConfigurationSettings.AppSettings("SmtpServer")

    Dim Message As New Mail.MailMessage()
    Message.From = "[e-mail]"
    Message.To = "[e-mail]"
    Message.Subject = "test"
    Message.Body = "salut je voulais savoir comment tu allais"

    ' You won't need the calls to Message.Fields.Add()

    ' Replace SmtpMail.SmtpServer = server with the following:
    Dim client As New SmtpClient(server) 
    client.Port = 587
    client.EnableSsl = true  
    client.Credentials = new System.Net.NetworkCredential(utilisateur,pass);

    Try
        client.Send(Message)
    Catch ex As Exception
        ' ...
    End Try

End Sub

If you replace the appsettings in the web.config with the following specific block, the SmtpClient will automatically configure itself accordingly:

<system.net>
   <mailSettings>
      <smtp from="[e-mail]">
         <network host="smtp.gmail.com" 
                  password="12345678" 
                  userName="[e-mail]"
                  enableSsl="true"
                  port=587/>
      </smtp>
   </mailSettings>
</system.net>

This would reduce your method to:

Sub SendSimpleMail()

    Dim Message As New Mail.MailMessage()
    Message.To = "[e-mail]"
    Message.Subject = "test"
    Message.Body = "salut je voulais savoir comment tu allais"

    Dim client As New SmtpClient() 

    Try
        client.Send(Message)
    Catch ex As Exception
        ' ...
    End Try

End Sub