October 29, 2007 11:42 AM PDT

FAQ: What the daylight saving shift means to you

Editor's note: This FAQ was originally published last spring. It's been updated to account for the fall changing of the clocks.

faq The fact that the U.S. is "falling back" a week late has left some folks with a few headaches, along with an unwarranted extra hour of sleep.

Standard time, which ordinarily would have kicked in at 2 a.m. Sunday, won't take place until next Sunday. Congress is to thank (or blame) for the change, which also meant daylight saving time started two weeks early. The thing is, computers weren't programmed with legislative intent in mind. Many gadget and software makers have issued patches to adjust to the change, though not everyone has installed the changes, and even people whose systems are now patched could see some calendar items showing up an hour off.

Here's a list of some commonly asked questions and answers regarding the time shift.

Q: So, daylight saving time is lasting an extra week. What's the big deal?
Most computers these days are set to automatically move forward each year to daylight saving and then back an hour in the fall. That's important, particularly for time-sensitive programs like calendars. Without a software update--and even with one in some cases--calendar items may be off by an hour.

So what do I need to do?
Microsoft released an update to Windows in November that prompts Windows to make the move. The company also has other patches available on its Web site. The patch was delivered in February to Windows XP Service Pack 2 users who have automatic updates turned on, but others may need to download the patch or manually adjust their PC's clock. Apple issued an update for Mac OS X Tiger in February 2006 and offered an updated patch last month for users of Tiger as well as Mac OS X 10.3 Panther.

Are all my calendar items going to be off by an hour?
No. Only calendar items during the extra daylight saving time (the additional three weeks of March and the last week of October) will be affected. Depending on how your business is managing things, many of your one-time calendar items might already be fixed, but it is worth taking a look at your calendar and double-checking the time for any crucial meetings.

Are there any precautions that I should take?
It's a good idea to start taking a look at your calendar for the next few weeks. Double-check when key appointments are supposed to be and note that in the text of the calendar item. That way, even if the time gets moved an hour off, you still know what time that appointment is supposed to be.

Is it just calendars that could be affected?
No. The move could impact time-sensitive applications other than calendaring, such as those that process sales orders or keep track of time cards. Gartner, for example, says the bug could lead to incorrect arrival and departure times in the travel industry and result in errors in bank transactions. In addition, trading applications might execute purchases and sales at the wrong time, and cell phone-billing software could charge peak rates at off-peak hours. Manufacturing operations that are computer-automated could also suffer.

What about my cell phone?
An update is available for Windows Mobile-based cell phones as well as Palm OS devices. Most standard cell phones set their clock based on the network time, so they should adjust automatically.

Are there other places around the world that are also making the early switch?
Yes. Canada is also changing its shift from daylight saving time, at least for the regions that observe daylight saving time, as are Western Australia, central Brazil and Tehran, Iran.

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Thank God the legislators will be affected too
Our legislators probably passed this with good intent but did bot do their homework (surprise, surprise, surprise!).
After all of the work we have had to put into it only to get it 90% fixed I take solace in the fact that those same legislators will most likely be just as affected by the messed-up meeting times as the rest of us.
Posted by fred dunn (793 comments )
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Saving time
Anyone rember War 2 when winter was on savings time and summer double savings time?

On computer adjustments, my Mac is already patched by Apple's excellent upgrades.

My real thoughts are on air travel to places that have not adjuste clocks. All this will be repeated in the fall when the whole thing is reversed.

Posted by bigduke (78 comments )
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Why DST?
DST was originally conceived as a way of saving energy. This made some sense in the early part of the last century, when people turned on a couple of 40-60 watt light bulbs after it got dark. Now, when you get home from work and there are several hours of hot sunlight left in the day, you have your programmable thermostat cool the house for an extra hour of expensive 5+ kilowatt air conditioning. Seems to me, if we really wanted to save energy, we'd reverse the process and have the sun set an apparent hour early.
Posted by kayoub (7 comments )
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Am I missing something?
Perhaps I am missing something but since my computer asjusts its time via the atomic clock on the Internet, won't that keep it correctly when DST kicks in and out?
Posted by ramudd (32 comments )
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No it won't.
The time you get from the time source is UTC also called GMT or Zulu time. The computer will successfully update that, but local time is obtained by applying a positive or negative offset to the UTC time, where the offset is determined by your local time zone and whether the computer believes that your region observes DST and what dates it transitions to and from DST.
Posted by PzkwVIb (462 comments )
Link Flag
Just ask all the Windows sysadmins...
...putting in extra hours this weekend.
Posted by ppgreat (1128 comments )
Link Flag
It means nothing to me I live in Arizona
Daylight savings time means nothing to me I live in Arizona. We don't have daylight savings time. We have 280 sunny days a year so we really don't need to save sunlight. They days are hot the nights are cooler so the night is a welcome relief.
Posted by davemesaaz (37 comments )
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For Eyes Only
I hear McCain is in top-secret talks with leading scientists trying to see if they can get daylight-wasting time established in Arizona
Posted by fmsorigaay (9 comments )
Link Flag
Oh it makes a BIG difference
I too live in Arizona. DST makes a big difference to me - twice a year, the TV guide simply can't get TV show times right on about half the channels. Some channels are more accurately reported than others.

But why does DST have this effect twice EVERY year :-(

Guess I'll just have to read a book, instead.
Posted by DryHeatDave (79 comments )
Link Flag
Easy solution for calendar users
Just make an "appointment" every day, say at 0600 that says "It's 0600". Now if on some date the times shift for some reason (such as the software doesn't set DST correctly) then you'd know that when you see an appintment in 0500 or 0700 that says "It's 0600" and you'd know exactly what the offset is.
Posted by hadaso (468 comments )
Reply Link Flag
Stock up on the Aleve...
...were all going to need it!
Posted by OneWithTech (196 comments )
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History lesson...s... ...about DST.........................
#1. DST was first implemented during WWII (World War II [Two (2)]. It was implemented so that factories could work during DAYLIGHT hours and [b]BLACK OUT[/b] when it got dark making them harder and less likely to be targets of bomb attacks. READ your history... ...while you STILL CAN!!!!!!!

#2. After WWII ended, the [i]ELITE[/i] groups...E.G.: Factory Execs, Government Officials, etc. (if you have a brain you get the picture)... decided to [u]KEEP[/u] DST in the summer so that they would have an [i]extra[/i] [b]hour[/b] to [b]PLAY [u]GOLF[/u][/b]!!!!! This is WHY we STILL have this archaic relic from the past. :|

#3. Back in the early 1970s (Circa 1975 or so?)DST was implemented for [u]ONE Whole YEAR[/u] during the ( [b]ECONOMICALLY '[i]fueled[/i]'[/b] ) "energy '[i]crisis[/i]'" we all went through then. Remember THAT????? It was found out [b][u]THEN[/u][/b] that absolutely [u]NOTHING[/u] changed a Blessed thing!!!!! Remember THAT????? Except that it was a painus in the anus for all.......just like now, only minus the computer "glitch" thing. :|

OK, [b]THINK[/b] about THIS:

First, we have the NSA [b]TELLING[/b] Windows users that they [i][b]MUST[/b][/i] "patch their computers" for [i]national security reasons[/i]. Remember THAT one?????? Since when does a 'gov' agency issue edicts like that????? I'll give you a clue: Since they started [b]ILLEGALLY[/b] SPYING on US Citizens, etc.!!! :|

Currently, we have this [i]reminder[/i](???) of a law enacted in [b][u]2005[/u][/b] (so far as anyone can determine, that is when a LOT of the spying either started or got very much WORSE!!!)

THEREFORE, one must deduce several things:

A. Microsoft [b]IS[/b] in bed with the regime running the U(F)SA [United [i]Fa

B. One must question/wonder what is [b][u]REALLY[u][b] contained within these "patches" that the US 'gov'/M$ [b][u]DEMANDS/FORCES[/u][/b] down computer users' throats.

NOW, realize that US citizens have the Constitutionally given RIGHT and [b]RESPONSIBILITY[/b] to question and CHALLENGE laws and the questionable practices they can sometimes spawn.

READ the Constitution for yourselves!!! Here's the Bill of Rights:


......Well, something [i]interesting[/i] just happened. Either my computer is messing up or that link no longer works. If you can't get to the Bill of Rights using that link try to find The US Constitution and it's Bill of Rights elsewhere IF you can and READ all of them that you can WHILE you can!!!!!!!!!!!!!!

BTW: Tin Foil Hats only make it EASIER for the "thought police" to home in on their wearers!!! Tin Foil Hats act like great big ANTENNAS!!!!!!!!! Remember having to put Tin Foil on the Antennas of your TVs to get better reception BEFORE the advent of CABLE and Satelite TV???????????? I do..........
Posted by btljooz (401 comments )
Reply Link Flag
My eyes now hurt after reading that extended bit of paranoia.
*puts head inside of a Faraday cage*
Posted by OscarWeb (76 comments )
Link Flag
The Time Change That Cried WOLF
Hasn't anyone heard of the NIST time program which works to synchronize your computer's time to the National Institute of Standards and Technologies atomic clock's time?

I've used it on Windows 95, 98se, XPsp2 and I have had no problems.

There is also a .pdf file to tell you how to use it.

The program takes a couple minutes to set up but after that you can set your system's clock any time you want.
Posted by Cuda 2 (1 comment )
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In the name of saving energy: Get real.
If desert politics gets its way, we will ignore
the number of overpowered fan cooled processors and video cards in computers that greatly embarrases any attempts to tinker with laws about clocks, incandescent lighting and power dedemand in California. I have yet to slow down DOS to keep a notebook fom frying my knees.
Posted by Martin Ozolin (13 comments )
Reply Link Flag
In the name of saving energy: Get real.
If desert politics gets its way, we will ignore
the number of overpowered fan cooled processors and video cards in computers that greatly embarrass political tinkerers with laws about clocks, incandescent lighting and power demand management in California. I have yet to slow down DOS to keep a notebook from frying my knees. Can computers replace highway transportation that's safer at night? The rest of us should use electric public transit with advanced baggage checking for circuit shopping.
Posted by Martin Ozolin (13 comments )
Reply Link Flag
No problems...
As expected, my WinXP computer appropriately changed time.

When I turned on my T-Mobile cell phone, it informed me that the time has been appropriately changed.

I was previously annoyed that our home thermostats didn't feature automatic DST changes, but that now turns out to be a good thing.
Posted by john55440 (1020 comments )
Reply Link Flag
Me too. Amazing isn't it...?
2:45 AM turned into 3:45 AM on my computer and on my cell
phone without me having to lift a finger (I did however have to
reset all my watches and clocks).
But for 45 minutes I WAS an hour behind the rest of the world!!!
Posted by fear_and_loathing (82 comments )
Link Flag
Spring forward, fall back...what a waste of time!
In the name of all that is holy, just leave the time set in the "spring forward" mode YEAR ROUND! Jeez, all this messing with the time twice every year, because of reasoning like: it helps farmers, and train schedules, and war factories, and helps keep the earth green. What kind of crazy nonsense is this, and what is wrong with us citizens that we continue to put up with this ridiculous tradition?
Posted by nycny (2 comments )
Reply Link Flag
Al Gore
inveneted DST to reduce teh carbon load on teh planet.
Posted by gggg sssss (2285 comments )
Reply Link Flag
The simplest solution
In your computer's clock applet (doesn't matter which OS you use) just disable DST correction and choose a timezone that gives the right time for you (assuming your clock was set correctly. Have it sync with a reliable time server and then choose the timezone that shifts the time to the correct value where you live). In winter time it would be your timezone and in summer time it would be a timezone one hour from your own timezone.

I live in Israel so in winter time I choose Jerusalem (GMT+0200) and in summer time I choose Bagdad (GMT+0300, and disable DST "correction", of course). That's all there is to it. The OS would serve the correct time to all the applications. The same has to be done for those applications who handle their time independently.

DST means only that at summer time you use the clock setings of another timezone.
Posted by hadaso (468 comments )
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