New Exchange Online Mailbox Auditing Signal: Visibility into IPM to Non-IPM Copy Activity (opens in new tab)

Background: IPM vs. Non-IPM Subtree Every Exchange Online mailbox is organized into two parts: IPM subtree (Interpersonal Message subtree) — the visible, user-facing part of a mailbox, designed for messages exchanged between human recipients. This includes Inbox, Sent Items, Deleted Items, Calendar, Contacts, Tasks, Notes, and any custom folders a user creates. Exchange mailbox auditing has always focused on activity within this area. Non-IPM subtree — a hidden folder structure used by Exchan...