Just before midnight on Wednesday, April 9, 2014, Pacific Daylight Time (PDT) a 911 call-routing facility in Englewood, Colorado, stopped directing emergency calls to eighty-one 911 call centers (Public Safety Answering Points or PSAPs) in seven states – California, Florida, Minnesota, North Carolina, Pennsylvania, South Carolina, and Washington. The outage was caused by a software coding error in the Colorado facility, and resulted in a loss of 911 service for more than 11 million people for up to six hours. Over 6,600 calls to 911 never reached a PSAP. Although, fortunately, it appears that no one died as a result, the incident – and the flaws it revealed – is simply unacceptable. Americans rely on 911 as a reliable way to communicate in an emergency, and lapses like this cannot be permitted.
According to the FCC report, this software issue was nothing more than a counter variable that reached a maximum value, and wasn't noticed for several hours due to various operational challenges.
For God's sake, stop researching for a while and begin to think!