Management of the Indonesia Stock Exchange (IDX) claimed that the trading error in stock market, affecting one-hour delay of trading opening this morning, was not caused by hackers or virus attack, but the datafeed (data dissemination) mistake. The problem did not occur in Jakarta Automated Trading System (JATS). IDX management needs two hours for resolving the incoming transactions from available log-in accounts. Trading activity started at 10 am Jakarta time today. At 3.24 pm, composite index of IDX fell further 0.6% to 5780.