Outlook for Office 365 duplicating a meeting when accepting

Question

Hello, we are running into an issue affecting 1 single user using the latest Outlook for Office 365 in Exchange Online.

When the user (let's call her Jane Doe) gets a meeting invite/request in Outlook on the desktop, she clicks accept meeting.

FOR SOME random meetings, this will then generate a duplicate meeting on her calendar, the duplicate changes the meeting owner to her Jane Doe, and re-sends this as a new meeting to the original list of attendees.

In other words:

1. Jane Doe receives an email in Outlook: "Meeting by John Smith" and the required attendees include Jane, Alice, and Bob
2. Jane clicks "Accept"
3. A new meeting appears on her calendar: "Meeting by Jane Doe" and the requires attendees are now John, Alice, Bob
4. The description is identical
5. John, Alice, and Bob get a new meeting invite and are confused.

Blurred image example: https://i.ibb.co/rc8YpM4/2023-03-20-12-15-15-Clipboard-Copy.png

This random intermittent issue occurs regardless of the following of the source meeting: whether or not a location is selected in the location field, whether or not a room resource is added as an attendee.

The user appears to have no Outlook rules in the desktop or web versions that could affect the calendar or moving/copying items in general. I checked MFCMAPI for corrupted rules, none exist.

I have wiped the user's local Windows profile clean and started fresh, and the issue appears again.

The user does use iOS mail client to view email on her phone, but not during the times that the issue occurs. She is strictly using the desktop Windows click and clicking the accept button in there.

Lastly I will state that I brought this issue to Office 365 support, even with "Advanced Support for Partners" which we do have, and after some back and forth they were no help. Any such help here from the community is greatly appreciated.

Answer 1

Hi @Nate Cohen ,

 

Based on your issue description, I have below suggestions:

 

“The user does use iOS mail client to view email on her phone, but not during the times that the issue occurs. She is strictly using the desktop Windows click and clicking the accept button in there.”

I can understand that she was not using the device when the issue occurs but considering that duplicated meeting issues are commonly found out to be related to mobile devices, I’d suggest removing the email account from the device temporarily to see if the problem persists.

 

“I have wiped the user's local Windows profile clean and started fresh, and the issue appears again.”

Have you tried it with the calendar in OWA, what's the result?

 

Besides, if the user in question is involved in any manager-delegate relationship, it’s recommended that you remove delegates temporarily and check if there would be any difference.

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