Outlook has a setting that allows it to add events to your calendar based on email messages. For example, if you purchased flight tickets, the flight times will be added to your calendar if this setting is enabled (which it is by default).

To turn it off:

  1. Click on the gear icon to open the settings panel and choose Calendar.
  2. Under Events from email, select the option Don’t add events to my calendar from email.
  3. Click Save.

Add events from email