Automatic Calendar Event Updates/Cancellations in Microsoft 365

Question

Hi,

One of our customers is experiencing an issue with Microsoft 365 where automatic calendar event updates and cancellations are being sent from one of the user accounts. The user has confirmed that they did not initiate these actions.

Here are the details:

• The issue is occurring with a single user account till this time.
• The automatic updates and cancellations are being sent to all attendees of the few random events.
• The user has not made any changes to the event or their calendar settings.

Any help or suggestions from the community would be greatly appreciated.

Answer 1

Hi @JanakKhadka

Welcome to our forum!

For better research, please provide more details about this case:

How did you send a meeting request (from Outlook or another calendar tool) and is there anything special about this meeting (e.g. it's a recurring meeting)?

If you create a normal meeting in Outlook, is it possible to reproduce this issue?

Here are some steps that may help resolve the issue:

• Check multiple devices: If you have an account configured on more than one device, try temporarily signing out of all other devices and using only one device to see if the issue persists.
• it may be affected by the add-ins or other 3rd tools, it's suggested to close other programs and run your Outlook in safe mode (Windows + R >type "Outlook.exe /safe">enter) to check if the issue has any difference.
• Examine Inbox Rules: Look into the Inbox rules on the Outlook desktop client. Sometimes rules can cause unexpected behaviors with calendar events. It's suggested to disable the rules temporarily to test(Rules>Manage rules and alerts>uncheck all rules).

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