There is a daylight saving time display "bug" that affects both Outlook for Windows and Outlook for Mac. It's not really a bug, but a limitation of the capabilities of the time scale and only affect people who start the week on Sunday. It's also more noticeable if you use Outlook for Windows and display two time zones and the default zone is west of the secondary zone, and to a lesser degree, when reverting to standard time. There are also display issues when the time zones switch to or from daylight saving time on different dates. Opening the appointment will show the correct time.
When you use a single time zone in Outlook and start the week on Sunday, the week the time changes, the scale will use the scale in effect at midnight Sunday.
When you use dual time zones in Outlook and the default zone is west of the secondary zone, an extra hour is added to the time scale offset for the Sunday DST goes into effect. If you view multiple dates and begin with that Sunday, the (incorrect) offset is used on the time scale so it appears Outlook has the times wrong.
For example, if your default time zone is Pacific and Eastern is your secondary time, when Sunday rolls around, the time scale incorrectly displays a 4 hr time difference all day. If you use a multi-day view with Sunday as the first day, the Sunday time scale is used, so it appears there is a 4 hour time difference each day.
This view anomaly occurs because the default is a zone west of the secondary and Outlook takes into consideration that DST goes into effect in the earlier time zone and adjusts the times using the wrong offset. The entire 24 hour period uses the same offset and the first day in the view determines the offset. This issue also affects the view when the time 'falls back' to standard time, but only if the dual time zones are 3 or more hours apart.
Fortunately Outlook uses GMT and time zone offsets to calculate appointment times and reminders are based off the default time zone, not the secondary zone, so it's unlikely to cause missed appointments (if you use reminders). When you open the appointments they appear at the correct time.
"Time heals all wounds" and it will fix this display problem - until then, use the Work Week view or select one or more days, beginning with Monday.
DST Starts or Ends on different dates
When the two time zones start and/or end Daylight Saving time on different dates, the time scale will vary during the delta period. For example, Helsinki starts DST at the end of March while the US makes the change 2 weeks earlier, so during this 2 week period, the usual difference will be off by an hour, depending on which zone is set as primary. In the fall, there is a 1 week lag where the times will be off by an hour.
Thanks! Wasted some time looking for an answer until I found your post. Really appreciate it!
Wow, I honestly hadn't expected to find a solution, but thanks to this page, I tried just changing the first day of week from Sunday to Monday and it fixed everything while still letting me show the whole week.
Specifically, in my case I wanted Eastern (-5) as my primary, and Arizona (-7, but no DST in summer, so 3 hours apart then) as my secondary, because I can never remember if they're 3 hours apart in summer and 2 in winter or the other way around. Outlook was showing them as 3 hours apart in winter (WRONG!!), just like shown in this article. I had reported this to MS via the Feedback Hub as a bug, but wasn't optimistic I'd find a fix. Sure enough, just changing the first day of week from Sunday to Monday, and boom, instantly fixed!!
Wow! thanks Guys for saving the daylights for me :) noticed the bug today morning and since then had spent countless hours changing every setting in Windows and outlook to get the 2nd time zone display correct ... but to no avail. Came across this article, change my start week to monday and bingo, problem solved.
Very helpful, thank you! However I'm in Italy and now on DST, UTC +2, instead of +1. I also track Eastern Daylight Time on my calendar. Even though the US changed time zones two weeks ago, and Italy changed theirs last Sunday, the time zone difference still shows as 5 hours instead of 6. I have the work week beginning with Monday. Any ideas how to fix?
>>Italy changed theirs last Sunday
8 days ago? If 2 days ago, use the work week view so the calendar starts on Monday.
As long as the time zones are correct (such as changing the zone you use instead of enabling the DST option), the time scale should be correct *provided* you do not have that Sunday set as the first day in the view.
Thanks so much for this! I installed some add-in from another site and that did not work. I'm sure this page gets the most visits around this time of year when the US goes into DST before Europe! Thanks again!
Extremely helpful! Your tip to show weekdays only vs full week starting Sundays worked like magic. I've been searching high and low for how to fix this. Thank you.
ANOTHER BIG THANKS! You saved a LOT of us a lot of time and headaches today with DST issues. Change start of week to Monday and all is fixed - both Mac and Windows Outlook. You are THE Exchange & Outlook authority as far as I'm concerned. You are the best!
Thank you so much! This has been driving me nuts for the last year or two -- relieved to have both an explanation of the cause and a solution :)