In Outlook, when a meeting is declined by attendees, it remains in the organizer's calendar as a record of the meeting. Unfortunately, there is no direct option for the organizer to delete a declined meeting from the Inbox without accessing the Calendar. This design choice may be intended to maintain a complete history of meetings and responses, but it can indeed be inconvenient for users who wish to manage their calendar more efficiently.
To delete a declined meeting, you will need to navigate to the Calendar view in Outlook, find the meeting, and delete it from there.
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