You can determine if hosts can send out email reminders for upcoming Webex Meetings, Webex Training sessions, or Webex Events that are scheduled on a Webex site. Email reminders are enabled by default, but you can turn this off.
Sign in to Webex Site Administration, and go to.
Scroll to Schedule Meeting Options, and under Meeting email reminders, select Off.
Scroll to the bottom of the page and click Update.