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Indiana DST problems (Windows) summarized

The following information applies primarily to Exchange and Outlook Calendars.  However, the general principals and concerns can be applied to other calendaring systems.

Please take the time to read the following email carefully if you deal with any kind of calendars.

Please be aware of the potential disruption to calendars caused by Indiana's switch to observing Daylight Saving Time on the morning of April 2nd. IT Staff across campus have been struggling with the severity of the impact to normal operations for some time now. From tests run by several departmental IT staff as well as central ITaP staff, we have collected the observations listed below:


A. Who this affects, and Symptoms of the problem:

 The vast majority of calendars on Windows Systems are affected because of the manner in which appointments are created and saved.

* Appointments created for the time period between April and October (while the machine is still in Indiana time (pre-DST)) will show up as having a one-hour offset once the computer is updated to observing DST. Appointments made AFTER the machine's time is set to Eastern time ARE CORRECT. Appointments made FROM machines which observe DST ARE CORRECT.

 * All day appointments, which are listed internally as an appointment from 12:01am to 11:59pm now show up as being from 1:01am to 12:59pm. This shows up as being a two-day appointment.

* Some recurring appointments show up correctly, but some do not: This is because of the time of year they were created. All should be treated as incorrect.

 Worst affected are Windows XP users who use calendars that are shared (for instance, users of the Purdue Exchange Server). Least affected are users of Mac OS 10.4.5 running Entourage 2004.

B. Non-solutions (Things that Campus IT organizations have tried and do not work):

 * Exporting the calendar to an internal format (such as .pst for Outlook): Exporting the appointments preserves the time stamp, and re-importing it just re-creates the problem faithfully.

* Exporting the calendar to a comma-separated-value file (CSV), and re-importing after changing the time: This preserves the "correctness" of the time, but strips out all extraneous information such as invitees, attendees, recurrences, etc. For instance, a recurring appointment is converted into a series of single appointments.

 * Changing time zones on machines: Servers as well as clients. This has no effect because the crucial timestamp is that of the machine AT the time of CREATION of the appointment. Subsequent changes do not affect the timestamp of the appointment, just when it shows up.

* Updating calendar items automatically: Since appointments are dependent on the local time of the actual event, updating all events will cause appointments between Indiana and Non-Indiana users to be INCORRECT. Automated solutions cannot decide the location of the event for you, only you have that information. It is our opinion that ANY automated solution could make calendar-related problems significantly worse and should be avoided.

 * Purdue and IU's IT staff have both been in touch with Microsoft, who is looking into this issue: Late yesterday, March 9th, Microsoft released a KnowledgeBase article that states that an automated solution will not be available... see: kb/915577/en-us

C. ECN's recommendations to minimize havoc created by incorrect appointment times: (Please note that these are not "fixes", but ways to help you deal with this issue)

 * Print a copy of your calendar either to pdf or paper. Go to File>Print

and from the Print Style select Weekly Style. Use a Start date of 4/1/2006 and an End date of 10/31/2006. This is just a safety measure.

 * Check your machine's Time Zone Setting. IMPORTANT: Please make sure you talk to your IT contact before making any changes to this setting. You can check this either by using Outlook's calendar: under "Tools> Options> Calendar Options> Time Zones." OR by checking the Date and Time Control Panel. Again, DO NOT MAKE CHANGES WITHOUT YOUR IT STAFF'S APPROVAL!

* Go through your calendar. As you see calendar items that you recognize and can be sure of, ensure the correct time, Click on the subject line, add the ACTUAL CORRECT TIME to the subject, save and close them.

 * As you see recurring appointments, add the ACTUAL CORRECT TIME to the subject, click on "Recurrence", click "Save and close". This updates the time CORRECTLY. A change may or may not happen, depending on the time of year of appointment creation.

* Opening All-Day items that incorrectly span two days, update the time, and clicking "Save and Close", updates the time stamp, and makes it CORRECT again.

 * The same can be done with appointments within Indiana, updating the subject, correcting the time, saving and closing will help you through events.

* If you notice appointments for events OUTSIDE of Indiana, be doubly aware of what the time of the appointment should be, and update appropriately.

 * As you work on your calendars, it may be helpful to view two different time zones. You can do this In Outlook by: click on Tools, Options, in the Preferences Tab, click Calendar Options, Time Zone. Label the Current Time Zone as EST and see that it is set to GMT-5, Eastern Time (US & Canada), Adjusted for DST. Enable "Show an Additional Time zone", Label that IND, set it to Indiana East (GMT-5), click OK. For an illustration, please see:

D. Summary:

This is an extremely complicated issue that does NOT have an easy solution. We (ALL of campus IT) are still trying to come up with something that might mitigate this situation, but as of right now, things do not look very good. Please be patient, since every person in the state of Indiana is going through the same process. Please understand that we are all in this together and we all must review our calendars carefully.  This is not a failing of ECN or ITaP.  It is a situation that was not taken into account in the design of some calendaring systems.  These comments are summarized and will be updated as we information is available at:

Updated 3/16/2006

Indiana University has provided the following documents on this topic that might be useful:

Last modified: 2006/08/09 12:59:0.837000 GMT-4 by Unknown
Created: 2006/08/09 12:59:0.837000 GMT-4 by brian.r.brinegar.1.


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