Why do scheduled events that repeat annually show up one month late on Outlook calendar?

I was able to resolve the issue!

Please note that in my Outlook Web Calendar my yearly recurring events were correct!

I resolved switching back to the "Legacy Outlook" for Mac interface.

1. Open New Outlook on Mac.
2. Click on "Help" in the top menu bar.
3. Select "Revert to Legacy Outlook" (or similar option).
4. Outlook will restart in the Classic version downloading all the contents/events/mails from server

Hi @Yunzi Shi

Thank you for posting your question in the Q&A Forum.

Regarding your observation about the January 31st event appearing in February, this is related to how the Outlook for Mac calendar engine processes yearly recurrence patterns for dates that do not occur in every month (such as the 31st).

In the New Outlook for Mac interface, the system’s logic for "All-day" recurrences may shift the display to the end of the following month to ensure the event remains visible within the calendar view. Please be assured that the event data remains correctly stored in the system; the shift is specific to the visual rendering in the Mac application. You can verify the intended schedule by viewing your calendar through Outlook Web Access (OWA).

To achieve your preferred display in the Outlook for Mac interface, you may consider the following adjustments:

• Assign a specific time instead of "All-day" to anchor the event to January 31st.
• Create or edit the series via OWA for accurate rendering across devices.
• Use Legacy Outlook for Mac, which handles yearly recurrences differently.

We appreciate you sharing your experience with the New Outlook interface. As we continue to improve the user experience, community feedback is essential to ensure our engineering teams are aware of your preferences for these display behaviors. We encourage you to submit this directly via Help > Feedback within your Outlook app, as this provides the necessary telemetry to address such rendering patterns in future updates.

We hope this information helps clarify how the calendar engine operates in this scenario.

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