Events declined in Outlook Calendar still appear in Apple Calendar

Hi @西湖IT管理员  

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

This behavior is usually caused by a sync issue between Legacy Outlook and Apple Calendar, where declined events are not properly updated on the Exchange server. 

May I know if the suggestions from Q&A Assist worked for you? In many cases, removing and re‑adding the Outlook/Exchange account on the Apple device resolves the sync issue. 

If the issue persists, you can try the following additional steps: 

1.Refresh from Calendar App 

-Open Calendar on macOS > View > Refresh Calendars (Command + R).

2.Open Calendar on macOS > Go to Calendar > Settings > Make sure Enable this account is checked for your Exchange account. 

3.Clear cached data 

Please make sure to back up the Calendar Cache file before deleting or moving it. 

-Quit the Calendar app. 

-Open Finder and navigate to: ~/Library/Calendars/Calendar Cache 

-Copy the Calendar Cache file to a safe backup location. 

-Delete or move the original Calendar Cache file. 

-Reopen Calendar and allow it to re-sync with Exchange. 

If you cannot locate the cache file, you may refer to Where does Calendar keep its caches? - Apple Community. 

Note: Microsoft is providing this information as a convenience to you. These sites are not controlled by Microsoft, and Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please ensure that you fully understand the risks before using any suggestions from the above link. 

4.If the above steps do not work, try declining the meeting directly in Outlook Web App. This ensures the server is updated correctly, and the decline propagates properly to Apple Calendar. 

I hope this helps.

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The issue of events declined in Outlook Calendar still appearing in Apple Calendar could be related to synchronization problems between the two platforms. When using Microsoft Exchange ActiveSync, sometimes calendar items may not sync correctly, leading to discrepancies such as declined events still showing up in other calendar applications.

Here are a few suggestions to troubleshoot this issue:

1. Recreate the ActiveSync relationship: This can help resolve any corrupted connections between the mobile device and the Exchange Online mailbox.
2. Check for updates: Ensure that both Outlook and Apple Calendar are updated to the latest versions, as updates often include bug fixes and improvements.
3. Remove and re-add the account: Sometimes, removing the email account from the Apple Calendar and re-adding it can resolve sync issues.
4. Disable any conflicting add-ins: If there are any add-ins in Outlook that might be affecting calendar synchronization, consider disabling them temporarily to see if it resolves the issue.
5. Restart devices: A simple restart of the devices can sometimes fix temporary glitches in synchronization.

If the problem persists, further investigation into the specific configurations of the accounts and devices may be necessary.