IT WORKS!

[Serializable]
    public class CWarkUser
    {
        public CWarkUser() { }
        public CWarkUser(string username, string userpassword, string usertag, bool isadmin, bool issuadmin)
        {
            UserName = username;
            UserPassword = userpassword;
            UserTag = usertag;
            IsAdmin = isadmin;
            IsSuAdmin = issuadmin;
        }
        public string ClientConfig = "CWark.config";

        public string UserName = "";

        public string UserPassword = "";

        public string UserTag = "";

        public bool IsAdmin;

        public bool IsSuAdmin;

        public void SaveUser(CWarkUser user)
        {
            BinList<CWarkUser>.Pack(ClientConfig, user);
        }
        public CWarkUser LoadUSerOnStartup()
        {
            return BinList<CWarkUser>.Unpack(ClientConfig);
        }
    }