What to do if you don’t want to be left in the dark by the changes to DST this year. As confusing as the beginning of daylight-saving time can be in general, it will be even more confusing this year to the IT managers who have to make sure that their companies’ computing systems aren’t left in the dark by a new schedule. The United States will enter DST at 2 a.m. local time March 11–three weeks earlier than nearly all computer hardware and software written since 1986 are expecting. And DST 2007 will end one week later than this hardware and software expect–at 2 a.m. local time Nov. 4. These changes were mandated by the Energy Policy Act of 2005. It’s impossible to predict exactly what problems the DST changes will cause, but it’s likely that there will be a few missed meetings and issues with some time-sensitive transactions. For many users, the biggest problems will be that meetings scheduled through Microsoft’s Outlook and other calendaring programs may appear to start an hour earlier than actually planned. And some all-day events may appear to span two days if calendaring programs misinterpret the start and end time of a meeting.