M365 Changelog: (Updated) Microsoft Defender for Office 365: Reported mailbox notifications messages subject change

MC790242 – Updated June 6, 2024: Microsoft has updated the rollout timeline below. Thank you for your patience.

Currently, in Microsoft Defender for Office 365, when a notification message is reported by an end user and arrives at the reporting mailbox, the subject lines begin with:

• “1|” to denote email messages reported as junk.
• “2|” to denote email messages reported as not junk.
• “3|” to denote email messages reported as phishing.

Moving forward, the subject lines of notification messages reported by end users will start with

• “Junk:” to denote email messages reported as junk.
• “Not junk:” to denote email messages reported as not junk.
• “Phishing:” to denote email messages reported as phishing.

This change is being made to ensure readability and enable you to create better rules inside your reporting mailbox.

The subject line for the team’s end-user reported notification messages will remain the same, continuing to start with “Security risk:”

When will this happen:

General Availability (Worldwide, GCC, GCC High, DoD): Microsoft will begin rolling out mid-June 2024 (previously late May) and expects to complete mid-July 2024 (previously mid-June).

How this will affect your organization:

After the rollout is complete, notification messages reported by end users will be affected. However, notification messages reported by end users prior to the rollout will remain unchanged.

What you need to do to prepare:

No action is required on your part. There won’t be any change to your existing user reported settings.