If you do not explicity specify the FROM address, you will receive an Object reference not set to an instance of an object. In a perfect world:
If From address not set, attempt to set it from the web.config: MailAttributes.From = new MailAddress((WebConfigurationManager.OpenWebConfiguration("~/Web.config").GetSectionGroup("system.net/mailSettings") as MailSettingsSectionGroup).Smtp.From);
If still no from address set, throw a friendly argument exception "From Address must be set to a valid e-mail address"
If you do not explicity specify the FROM address, you will receive an Object reference not set to an instance of an object. In a perfect world: