Software Update Crashed Stock Exchange

Wednesday’s four-hour outage at the New York Stock Exchange was caused by a software upgrade made the night before, the exchange announced Thursday. In the description of the incident, the stock exchange says it began a software release Tuesday night. When people had connection issues Wednesday morning, NYSE techs tried to fix them, but that resulted in additional communications issues mid-morning. They made the decision to suspend trading because customers were still reporting “unusual system behavior.”