Symantec forced to write off US$10 million in revenue after glitch in sales system. Glitch prevented some consumers from activating Norton antivirus software at the time they bought it. Problem affected less than half a percent of customers, CEO Enrique Salem said in an interview. The issue was disclosed Wednesday in company’s quarterly earnings announcement. The company’s revenue for the quarter, ended Oct. 1, was $1.48 billion, pretty much level with a year earlier. But storage and services groups dipped by 1 percent and 11 percent, respectively.”]