 A cybersecurity company, CrowdStrike, says the reason for the disruption appears to be a defect in its software update for users of Microsoft Windows. It said a fix had been deployed. Donald Trump has officially accepted the U.S. Republican's presidential nomination and has told the party's convention that if he's elected in November, he will work for all of America, not just half of it. But he launched a fierce attack on President Biden's record.