M365 Roundup, March 2025: Exchange Starts Counting Your Outbound Email

March 2025 is a licensing-and-limits month. Exchange Online begins enforcing a hard daily cap on external recipients per tenant, complete with a formula worth bookmarking, and E5 Security lands as an add-on for Business Premium, reshaping the upsell conversation for SMB-focused MSPs. Add the slow retirement of the Report Message add-ins and a Conditional Access control heading for end of life, and there is real housekeeping in this batch. The full month, grouped by product.

Microsoft Teams#

Shared content stops auto-appearing for town hall attendees#

Currently, when a presenter shares content, it is automatically displayed for attendees. With this update, shared content first appears in the Manage screen's left panel alongside other presenters, and an organizer or presenter must manually bring it on screen. That gives event teams control over the attendee experience and prevents unintended interruptions. Rollout: mid-April 2025, completing by late April 2025.

Users can report security concerns about external collaborators#

Teams users will be able to report security risks and concerns involving external users outside the organization in one-on-one chats, group chats, and meeting chats. Rollout: early May 2025, completing by mid-May 2025.

Live chat reaches general availability in the US#

Live chat in Microsoft Teams lets small businesses provide quick customer service by allowing website visitors to chat directly with their team in Teams. Companies are limited to a maximum of 25 users for Live chat. Generally available now in the US, with the rest of the world following by end of March 2025. A video overview is available here: Teams Live chat walkthrough (opens in new tab).

Chat @nearby connects you with colleagues in the building#

You can now connect with physically nearby colleagues via Teams chat using @nearby. By showing which colleagues are close, the feature nudges impromptu in-person connections, a spontaneous lunch or a quick hallway chat. Public preview in April 2025.

The Files tab in channels becomes the Shared tab#

After this rollout, users can still work with files and folders in the SharePoint document library linked to the channel. All existing functionality from the Files tab lives on in the In library view of the new Shared tab. Rollout: mid-May 2025, completing by mid-June 2025.

Bookings adds a Queue view for Teams Premium users#

Queue gives schedulers and admins real-time visibility and control over incoming appointments: a consolidated, chronological view of each day's appointments across the booking pages they manage, the ability to reassign delayed appointments to available staff, and self-service assignment so staff can pick up unassigned appointments on busy days. SMS and email reminders can be sent straight from the queue view to keep customers informed. Rollout: mid-April 2025, completing by late April 2025.

Microsoft Outlook#

Reminders for past events will dismiss themselves#

The Reminder window in new Outlook for Windows pops up over email or calendar when a scheduled event is about to start. Microsoft is enabling the "Automatically dismiss reminders for past events" option for all users, which stops reminders from appearing for events that already happened. Rollout: late April 2025, completing by early May 2025.

Report Message and Report Phishing add-ins enter maintenance mode#

The Report Message add-in and Report Phishing add-in are now in maintenance mode: no further improvements, functional until eventually retired, and new improvement requests will be rejected. Details and FAQ: Transition from Report Message or the Report Phishing add-ins (opens in new tab).

Two situations to plan for:

• If you run the Report Message or Report Phishing add-in, users see two reporting options in Outlook: the add-in and the built-in Report button. Removing the built-in button while keeping the add-in is not possible. Microsoft documents removing the add-in (opens in new tab).
• If you use a third-party reporting add-in, suppress the built-in button like this:
  1. Go to Microsoft Defender > User reported settings (opens in new tab).
  2. Select Monitor reported messages in Outlook.
  3. Select Use a non-Microsoft add-in button.
  4. In the Reported message destination section, configure:
     • For Send reported messages to, select either My reporting mailbox only or Microsoft and My reporting mailbox.
     • For Add an Exchange Online mailbox to send reported messages to, specify an existing internal reporting mailbox to hold user reports from the third-party add-in.

Status: generally available.

Message recall comes to Outlook on iOS and Android#

Users get the option to request a recall attempt for a sent email from the mobile app, an extra layer of control for messages sent in error. Rollout: early March 2025, completing by late March 2025.

New Outlook for Windows enables bulk .eml import#

Bulk import of .eml files will be on by default in new Outlook for Windows, simplifying migration and consolidation of email data. The steps:

1. Go to Settings > General > Import.
2. Select Start import.
3. Select the folder containing the .eml files.
4. Select the destination account and folder.
5. Select Import.

Rollout: mid-March 2025, completing by late March 2025.

Microsoft 365 Apps and OneDrive#

Office apps will prompt unenrolled users to back up to OneDrive#

For organizations with users not yet enrolled in Known Folder Move, a message reading "BACK UP THIS DOCUMENT: Share and work with others in this and other files using OneDrive" will appear in familiar desktop apps. After selecting Open OneDrive, users pick the folders they want backed up. Rollout: early April 2025, completing by early May 2025.

OneDrive folder shortcuts get a clearer naming convention#

New folder shortcuts added to OneDrive > My Files will include their source. Examples:

• A shortcut to a folder named Project Files on a SharePoint site named Marketing Team appears as Marketing Team - Project Files.
• A shortcut to a folder named Blog post from Mona Kane's OneDrive appears as Mona Kane's files - Blog post.

Key points:

• The new naming logic applies only to shortcuts created after the rollout.
• Existing shortcuts keep their current names.
• The change shows up in OneDrive for the web, OneDrive for iOS and Android, File Explorer, Mac Finder, and Microsoft Teams.
• It is on by default.

Rollout: mid-March 2025, completing by mid-April 2025.

Microsoft Entra ID#

"Require approved client app" retires in March 2026#

The "Require approved client app" control in Entra Conditional Access will be retired in March 2026. Microsoft recommends moving those policies to the "Require application protection policy" grant control, which provides the same data loss protection with additional benefits. Worth fixing now rather than during a deadline scramble next year.

The "More information required" registration screen gets friendlier#

Microsoft is updating the user experience shown during authentication method registration to make the language more approachable. Rollout: early March 2025, completing by late March 2025.

Old experience:

New experience:

Microsoft Copilot#

Interpreter agent brings live translation to Teams meetings#

The Interpreter agent enables real-time speech-to-speech interpretation in multilingual Teams meetings, letting each participant speak and listen in their chosen language. Users can opt in to have Interpreter simulate their own voice, which helps others identify who is speaking, or pick from a set of default voices. Rollout: late March 2025, completing by early April 2025.

Copilot Chat sessions become searchable#

Before this rollout, finding an old Copilot chat session meant skimming and scrolling. After it, users type keywords and matching sessions appear as they type. Rollout: early April 2025 (previously early March), completing by mid-April 2025 (previously mid-March).

Copilot pay-as-you-go billing arrives in the M365 Admin Center#

Admins will be able to manage billing for Microsoft 365 Copilot Chat directly in the M365 Admin Center instead of navigating to the Power Platform admin center: set up billing, turn it off, edit billing for unhealthy subscriptions, and view costs. Find it under Copilot > Settings > Copilot pay-as-you-go billing. Rollout: late March 2025.

PowerPoint Copilot learns your brand#

Microsoft 365 Copilot in PowerPoint will create presentations using the organization's brand images, pulled from an organizational asset library (OAL) in SharePoint or a Templafy library. References:

• Keep your presentation on-brand with Copilot (opens in new tab)
• Connect organizational asset libraries to Copilot (opens in new tab)
• Create an organization assets library (opens in new tab)

Rollout: late March 2025, completing by early April 2025.

Admin and licensing#

Exchange Online enforces tenant-level outbound email limits (TERRL)#

To reduce misuse of Exchange Online resources and protect service availability, Microsoft is introducing the Tenant External Recipient Rate Limit (TERRL), a cap on how many external recipients a tenant can email per day. Exceed it, and further messages to external recipients are blocked until the trailing 24-hour volume drops below quota.

The quota scales with purchased email licenses:

500 * (Purchased Email Licenses^0.7) + 9500

A new report tracks usage in the Exchange admin center under EAC > Reports > Mail flow > Tenant Outbound External Recipients Rate: current external recipient volume, the tenant's daily quota, how much is used, and how many recipients were blocked if the limit was exceeded. The report also shows whether enforcement is enabled; tenants with more than 500 email licenses show "Disabled" until May 1, 2025, when enforcement starts for them.

Enforcement phases in by tenant size:

For MSPs, the action item is identifying clients that do legitimate bulk external sending, newsletters, invoicing systems, notification platforms, before their phase date arrives.

E5 Security becomes a Business Premium add-on#

Microsoft 365 E5 Security is now available as an add-on to Microsoft 365 Business Premium. It layers on Microsoft Entra ID Plan 2, Microsoft Defender for Identity, Microsoft Defender for Endpoint Plan 2, Microsoft Defender for Office 365 Plan 2, and Microsoft Defender for Cloud Apps. For SMB clients who outgrew Business Premium's security ceiling but cannot justify full E5, this is the middle path that did not exist before. Full announcement: Microsoft 365 E5 Security is now available as an add-on to Microsoft 365 Business Premium (opens in new tab).