Encrypt the password string in web.config
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How can I encrypt the password string in web.config?

    <system.net>
        <mailSettings>
          <smtp deliveryMethod="Network">
            <network host="smtp.gmail.com" userName="guess@gmail.com" password="test" port="587" />
          </smtp>
        </mailSettings>
    </system.net>

What is the correct way to do it?