Outlook calendar shows one-hour off before daylight saving?

Question

Hi,

I'm trying to subscribe to a calendar from this URL:

webcal://myau.ento.com/api/staff/calendar/c65b0585da47932.23970544(Timezone is in UTC+10 Australia, AEST).

I've set up my outlook.com to be in the same timezone (Melbourne / UTC+10). However when I subscribed to this calendar, the 3 & 4 Oct event is off by an hour. The 15 Oct is correct (daylight saving starts on first Sunday of October, timezone becomes AEDT). I thought the .ics is wrong or contains missing information about the daylight saving but they are there.

What makes me confused:

Outlook (both .com and app) shows the event times correctly if I import the .ics file
Google Calendar displays them correctly both with subscribing to calendar and import

The contents of the .ics file is below (I put newlines for readability)

BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//c65b0585da47932.23970544//NONSGML kigkonsult.se iCalcreator 2.18/
/
METHOD:PUBLISH
X-ORIGINAL-URL:webcal://myau.ento.com/api/staff/calendar/c65b0585da47932.23
970544
X-WR-CALNAME:Roster Calendar: Arlyn A
X-WR-CALDESC:Shift and leave details for Arlyn A
X-WR-RELCALID:c65b0585da47932.23970544
X-WR-TIMEZONE:Australia/Hobart

BEGIN:VTIMEZONE
TZID:Australia/Hobart
X-LIC-LOCATION:Australia/Hobart

BEGIN:STANDARD
DTSTART:20250406T030000
TZOFFSETFROM:+1100
TZOFFSETTO:+1000
TZNAME:AEST
RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=1SU
END:STANDARD

BEGIN:DAYLIGHT
DTSTART:20241006T020000
TZOFFSETFROM:+1000
TZOFFSETTO:+1100
TZNAME:AEDT
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=1SU
END:DAYLIGHT

END:VTIMEZONE

BEGIN:VEVENT
UID:Shift80161850@c65b0585da47932.23970544
DTSTAMP:20241001T013833Z
DESCRIPTION:60m
DTSTART;TZID=Australia/Hobart:20240902T090000
DTEND;TZID=Australia/Hobart:20240902T170000
LOCATION:Head Chef - Southbank
SUMMARY:Shift: 09:00-17:00 - Head Chef
END:VEVENT

BEGIN:VEVENT
UID:Shift80200008@c65b0585da47932.23970544
DTSTAMP:20241001T013833Z
DESCRIPTION:60m
DTSTART;TZID=Australia/Hobart:20240903T090000
DTEND;TZID=Australia/Hobart:20240903T170000
LOCATION:Head Chef - Southbank
SUMMARY:Shift: 09:00-17:00 - Head Chef
END:VEVENT

BEGIN:VEVENT
UID:Shift81192653@c65b0585da47932.23970544
DTSTAMP:20241001T013833Z
DESCRIPTION:15m
DTSTART;TZID=Australia/Hobart:20241003T090000
DTEND;TZID=Australia/Hobart:20241003T170000
LOCATION:Head Chef - Southbank
SUMMARY:Shift: 09:00-17:00 - Head Chef
END:VEVENT

BEGIN:VEVENT
UID:Shift81192670@c65b0585da47932.23970544
DTSTAMP:20241001T013833Z
DESCRIPTION:15m
DTSTART;TZID=Australia/Hobart:20241004T090000
DTEND;TZID=Australia/Hobart:20241004T170000
LOCATION:Head Chef - Southbank
SUMMARY:Shift: 09:00-17:00 - Head Chef
END:VEVENT

BEGIN:VEVENT
UID:Shift81194648@c65b0585da47932.23970544
DTSTAMP:20241001T013833Z
DESCRIPTION:60m
DTSTART;TZID=Australia/Hobart:20241015T090000
DTEND;TZID=Australia/Hobart:20241015T170000
LOCATION:Head Chef - Southbank
SUMMARY:Shift: 09:00-17:00 - Head Chef
END:VEVENT

END:VCALENDAR

Was there something in the ics file that makes this weird issue?

Answer

Hi @Lyon

Welcome to our forum!

Does the issue occur on the Outlook desktop client? To further confirm if the issue is more related to Outlook desktop client, if possible, please log in to your web mail and do the same test to check if the issue persists.

What is the version of your Outlook? It is recommended that you please check the Outlook client version (File>Office Account>Product Information) and try to upgrade to the latest version to see if the problem is resolved.

However when I subscribed to this calendar, the 3 & 4 Oct event is off by an hour. The 15 Oct is correct (daylight saving starts on first Sunday of October, timezone becomes AEDT).

The .ics file appears to handle this correctly, but there might be an issue with how Outlook interprets these transitions. It is suggested please re-subscribe to the calendar to see the issue if persists.

In addition, there is an article mentioned This problem occurs because of how Outlook calculates these differences for display in the Outlook user interface. And its workaround is to use the Work Week view. It is recommended that please change Calendar View to Week to see if the problem persists.

More information: Additional time zone shows a one-hour offset on DST start day in Outlook - Outlook | Microsoft Learn

If all above do not work, as i know: Microsoft is researching this problem and will post more information in this article when the information becomes available. If there is any update, I will post here as soon as possible.

Hope it helps!

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

Note: Please follow the steps in our [documentation] to enable e-mail notifications if you want to receive the related email notification for this thread.

Answer

Hi Joan, thank you for the answer.

Switching to Work Week still shows the one hour discrepancy I'm afraid (notice how the calendar thinks it starts at 10am even though it's supposed to be 9am-5pm:

sshot-1

The issue happens on both Outlook.com and Outlook app (I also asked a couple of friends with Outlook to try subscribing to the calendar and found the same thing).

I assume I have the latest version but here they are:

You have Microsoft Outlook Version 1.2024.925.200 (Production).
Client Version is 20240920004.12.
WebView2 Version is 129.0.2792.65.

I've also tried resubscribing to the calendar for the past week several times to test. I guess if you said that the .ics file is correct and that importing it solves the issue (and Google Calendar also works), I guess it's probably a bug of some sort in Outlook and will have to wait until Microsoft finds a solution?

Share via

Outlook calendar shows one-hour off before daylight saving?

2 answers

Your answer