private void SaveUser(User user)
        {
            XmlDocument dom = new XmlDocument();

            XmlHelper.CheckXMLFile(PublicParams.xmlHistory);
            dom.Load(PublicParams.xmlHistory);
            XmlNode nodeRoot = dom.SelectSingleNode("Root");

            ClearLastUserName(ref nodeRoot);
            XmlElement xe        = dom.CreateElement("User"); xe.SetAttribute("Last", "true");
            XmlElement name      = dom.CreateElement("Name"); name.InnerText = user.Name.Trim(); xe.AppendChild(name);
            XmlElement pwd       = dom.CreateElement("Pwd"); pwd.InnerText = CryptHelper.Encrypt(user.Pwd.Trim()); xe.AppendChild(pwd);
            XmlElement remember  = dom.CreateElement("Remember"); remember.InnerText = user.Remember.ToString(); xe.AppendChild(remember);
            XmlElement autoLogin = dom.CreateElement("AutoLogin"); autoLogin.InnerText = user.AutoLogin.ToString(); xe.AppendChild(autoLogin);

            nodeRoot.AppendChild(xe);
            dom.Save(PublicParams.xmlHistory);
        }