Daylight Saving Time will start on March 11, three weeks earlier than usual, and it will end on November 4, 1 week later than usual. This causes some interesting problems for your Windows XP computer. Watch your appointments very carefully during those weeks!
During those three weeks, your computer should show the correct time. Microsoft has released updates for the computer’s clock that have probably been installed automatically as Critical Updates. (Your computer clock would be off by an hour for those weeks without the patches.) I don’t expect that to be an issue for most people.
The difficult problem is with calendar programs, especially Outlook. After applying the automatic patches to Outlook, I think new appointments added to Outlook will appear at the correct time, instead of being an hour off. If you had entered appointments before applying the patches, they may not be listed correctly.
Businesses running Small Business Server 2003 use Microsoft Exchange Server 2003 to run their calendars in Outlook. Microsoft has thoroughly mucked up the process of updating existing calendar entries and patching Exchange. This page devoted to the DST updates has been updated and changed far too often: new patches get released that require uninstalling old patches, then running arcane command line utilities; then something else comes along that seems to make all that work irrelevant. There are patches for servers, patches for workstations, patches for Exchange, patches for mobile phones, and they’re constantly changing. It’s a mess.
The SBS community is thoroughly pissed. This influential SBS blogger has given up. Take a look at the explanation of how to run just one of the myriad tools that have been released and you’ll understand where the feeling of despair comes from. Or compare this summary on February 20 with an equally overwhelming and confusing update two days later.
On March 11, you cannot trust your calendar. I have no answer. Please, please, do your own due diligence, show up in court on time, don’t miss appointments!