http://americasmarkets.usatoday.com/2015/07/08/nyse-mysteriously-halts-all-trading/
All trading on the New York Stock Exchange is halted Wednesday for unknown internal technical reasons – heaping yet another worry onto investors already rattled by global economic concerns.

All trading on the New York Stock Exchange is halted Wednesday for unknown internal technical reasons – heaping yet another worry onto investors already rattled by global economic concerns.