NEW YORK — The reason behind the shutdown wasn’t quite as exciting as hackers, Bane or aliens — the New York Stock Exchange said the real reason behind their shutdown was a faulty software release.
The stock exchange began a software release the night before the shutdown. At 7 a.m. Wednesday, communication issues were already being detected between customer gateways and the trading unit, according to a press release. Stock exchange officials realized these issues were being caused by customer gateways that were not compatible with the new software.
By 9:30 a.m., an updated, correct version of software was implemented. However, this update to the gateways caused more communication issues between the gateways and trading units.
At 11:09 a.m., NYSE made an announcement that a technical issue was being investigated. At 11:32 a.m., NYSE and NYSE MKT were actively trading, though customers were reporting unusual system behavior.
NYSE and NYSE MKT then suspended trading, though NYSE ARCA, Arca Options and NYSE AMEX Options were not impacted and continued operating normally.
NYSE and NYSE MKT canceled all open orders and worked with customers to reconcile orders and trades, and restarted all customer gateways.
A complete restart was ordered so that all systems affected could resume by 3:10 p.m. Everything went as planned: trading resumed, and the closing auctions were executed normally.