Microsoft Defender for Office 365
Email and collaboration

Defender For Office 365 Whats New

In brief

The EmailPostDeliveryEvents table documentation now includes the ApproverUpn field, which identifies the approving user or administrator.

What Defender admins need to know

Administrators can use this field in Advanced Hunting to identify who approved an email post-delivery action.

Summaries are generated from the documentation change itself.

Documentation change

The comparison below shows only the changed extract. Use the full-page view for complete context.

author: chrisda ms.author: chrisda ms.localizationpriority: medium ms.date: 2026-10-05T00:15T00:00:00.0000000Z ms.collection:

  • m365-security
  • tier1

October 2026

  • New ApproverUpn field in the EmailPostDeliveryEvents table: The EmailPostDeliveryEvents table in Microsoft Defender XDR Advanced Hunting now includes the ApproverUpn field. This field identifies the user or administrator who approved a remediation action, helping security teams investigate and audit post-delivery email actions more efficiently.
  • Expanding user reporting in Teams to include meetings: Users can report scheduled or Meet now Microsoft Teams meetings or individual meeting participants as a security concern during or after the meeting. Users can also report a meeting participant that was incorrectly identified as suspicious as not a security concern. Depending on Teams user reported settings, reported meeting and participant metadata is sent to the specified reporting mailbox, to Microsoft, or both.

September 2026