How to enable SSL for SmtpClient in Web.config

I have a dirty workaround (until .NET 4.0 comes out). Instead of changin my code it relies on the used port to determine if SSL is required or not.

var client = new SmtpClient();
client.EnableSsl = client.Port == 587 || client.Port == 465;
// This could also work
//client.EnableSsl = client.Port != 25;

I said it was a dirty hack, but it working fine for the different configurations that we encounter.

For .NET 3 and earlier: You can't. You have to manage it by hand.

For more information you can see https://blogs.msdn.microsoft.com/vikas/2008/04/29/bug-asp-net-2-0-passwordrecovery-web-control-cannot-send-emails-to-ssl-enabled-smtp-servers/.

For .NET 4: You can.

See http://theoldsewingfactory.com/2011/01/06/enable-ssl-in-web-config-for-smtpclient/

<configuration>
    <system.net>
        <mailSettings>
            <smtp deliveryMethod=”network”>
                <network host="localhost"
                         port="25"
                         enableSsl="true"
                         defaultCredentials="true" />
            </smtp>
        </mailSettings>
    </system.net>
</configuration>