QMy computer automatically adjusts its clock for daylight saving time, but now DST will arrive three weeks earlier. How can I update it? AFrom now on, daylight saving time will kick in on the second Sunday in March instead of the first Sunday in April; it will also end one week later than before. This change, imposed by the Energy Policy Act of 2005, will confuse computers programmed to spring forward and fall back on the old schedule.

If you're running Windows XP or Mac OS X 10.3 or 10.4 and use the automatic-update features of those operating systems, you're fine -- Apple and Microsoft have already released patches for them. Windows Vista shipped with the correct DST schedule.

If, however, you use an older system, you're on your own. Microsoft has provided instructions how to edit the Windows registry in earlier versions of Windows (http://support.microsoft.com/kb/914387), but it is easier to use the free, unofficial updater released by IntelliAdmin, a Web site for Windows administrators. Visit http://www.intelliadmin.com/downloads.htm and search for "Daylight Saving Time Fix."

I could not find any fix for older editions of Mac OS X simpler than adjusting a Mac's clock manually in the Date & Time control panel.

AOL has started putting an ad at the end of every message I send from my account, even though I pay for it. This is really tacky.

No argument about that-- if you pay for your account, you shouldn't have a "Check Out Free AOL" ad stuck on your outgoing mail. But AOL has decided otherwise.

You can, however, eliminate these ads by using a non-AOL e-mail program -- for instance, Mozilla Thunderbird, Microsoft's Outlook Express or Apple's Mail -- to check your AOL mail. Visit http://about.aol.com/faq/openmailaccess for instructions on setting up your software.

Rob Pegoraro attempts to untangle computing conundrums and errant electronics each week. Send questions to The Washington Post, 1150 15th St. NW, Washington, D.C. 20071 or robp@washpost.com.