How to delete a meeting occurrence from a former user?

Hi @Blair, Mark,

May I ask whether you want to completely remove the meeting and its associated meeting data, or whether you simply want to stop receiving future invitations and reminders?

If you only want to stop receiving future notifications, you can open your Calendar, select the meeting, and choose Decline for the series. This will remove it from your calendar and prevent future reminders.

If you want to cancel the meeting completely for all attendees, the available options depend on whether the organizer's mailbox still exists.

Could you please provide the following information?

• Does the meeting have any co-organizers?
• Can you check with your IT administrator whether Dorian West's mailbox is still available, has been converted to a shared mailbox, or has already been deleted?

Typically, when a recurring meeting was created by a former employee, the resolution depends on the status of the organizer's mailbox.

• If the mailbox is still available (or has been converted to a shared mailbox), an administrator can be granted access to the mailbox and use Outlook to cancel the recurring meeting series or remove specific occurrences.
• If the mailbox has already been deleted, attendees generally cannot cancel a meeting series they do not own. In that case, an Exchange Online administrator may need to remove the meeting using the appropriate admin tools.
• If the goal is simply to stop future meetings, another option is to create a replacement meeting under a new organizer and notify attendees that the original recurring series should be removed or ignored.

Please let me know the information above, and I'll be happy to suggest the most appropriate approach.