public SendResponse InjectMessage()
        {
            var html = MessageTemplate.BuildHtmlMessage(_body);

            if (_socketLabsClient == null)
            {
                _socketLabsClient = new SocketLabsClient(this.ServerId, this.InjectionApiKey);
            }

            var message = new BasicMessage();

            message.Subject       = this.Subject;
            message.HtmlBody      = html;
            message.PlainTextBody = _body;
            message.From.Email    = this.Sender;

            foreach (var recipient in this.Recipients)
            {
                message.To.Add(recipient);
            }

            return(_socketLabsClient.Send(message));
        }