You may have started receiving messages with the subject of "Your Daily Briefing" from Cortana (email@example.com). The Daily Briefing emails are personal and private and only sent to you - no one else can see them including your IT Admin or your manager. According to Microsoft, the Briefing emails can help you plan for meetings by showing you related tasks or documents, manage your tasks and make the most of your time. See Privacy guide for Briefing emails for more information.
You can turn off the daily briefings by clicking the Unsubscribe link in the Daily Briefing email message.
Shared accounts will need to login to OWA in order to unsubscribe.