BF2Statistics.Gamespy.GamespyUtils.DecodePassword C# (CSharp) Method

        public static string DecodePassword(string Password)
        {
            // Convert Gamespy Base64 to Standard Base 64
            StringBuilder builder = new StringBuilder(Password);
            builder.Replace('_', '=');
            builder.Replace('[', '+');
            builder.Replace(']', '/');

            // Decode passsword
            byte[] PasswordBytes = Convert.FromBase64String(builder.ToString());
            return Encoding.UTF8.GetString(GsPassEncode(PasswordBytes));
        }

        /// <summary>
        /// Whenever the "newuser" command is recieved, this method is called to
        /// add the new users information into the database
        /// </summary>
        /// <param name="Recv">Array of parms sent by the server</param>
        private void CreateNewUser(Dictionary <string, string> Recv)
        {
            // Make sure the user doesnt exist already
            try
            {
                using (GamespyDatabase Database = new GamespyDatabase())
                {
                    // Check to see if user exists
                    if (Database.UserExists(Recv["nick"]))
                    {
                        Stream.SendAsync(@"\error\\err\516\fatal\\errmsg\This account name is already in use!\id\1\final\");
                        Disconnect(5);
                        return;
                    }

                    // We need to decode the Gamespy specific encoding for the password
                    string Password = GamespyUtils.DecodePassword(Recv["passwordenc"]);
                    string Cc       = (RemoteEndPoint.AddressFamily == AddressFamily.InterNetwork)
                        ? Ip2nation.GetCountryCode(RemoteEndPoint.Address)
                        : Program.Config.ASP_LocalIpCountryCode;

                    // Attempt to create account. If Pid is 0, then we couldnt create the account
                    if ((PlayerId = Database.CreateUser(Recv["nick"], Password, Recv["email"], Cc)) == 0)
                    {
                        Stream.SendAsync(@"\error\\err\516\fatal\\errmsg\Error creating account!\id\1\final\");
                        Disconnect(6);
                        return;
                    }

                    Stream.SendAsync(@"\nur\\userid\{0}\profileid\{0}\id\1\final\", PlayerId);
                }
            }
            catch (Exception e)
            {
                // Check for invalid query params
                if (e is KeyNotFoundException)
                {
                    Stream.SendAsync(@"\error\\err\0\fatal\\errmsg\Invalid Query!\id\1\final\");
                }
                else
                {
                    Stream.SendAsync(@"\error\\err\516\fatal\\errmsg\Error creating account!\id\1\final\");
                    GpcmServer.Log("ERROR: [Gpcm.CreateNewUser] An error occured while trying to create a new User account :: " + e.Message);
                }

                Disconnect(7);
                return;
            }
        }