Engage - Direct Message Injection Update - Dec 2025

Service Update

Availability	December 18th, 2025
Product(s)	Engage
Who's affected	All Engage customers using Direct Message Injection (DMI) for phishing simulations in Microsoft 365 multi-tenant environments.

Overview

Mimecast is pleased to announce an enhancement to the Direct Message Injection (DMI) feature in Engage. Previously, only one integration for direct message injection could be configured per account. With this update, customers can now configure up to 25 DMI connectors per account, enabling greater flexibility and scalability for organizations managing multiple tenants.

What's changing

• Multiple DMI Connectors per Account:

You can now configure up to 25 DMI integrations within a single Engage account, supporting multi-tenant scenarios and complex organizational structures.

• Improved Management:

Administrators can create, update, and manage several DMI integrations, each mapped to different tenants or environments as needed.

• Enhanced Auditability:

Audit logs will capture when DMI integrations are added, updated, or deleted, as well as when phishing campaigns are created and delivered, or if errors occur.

Recommended actions

• Review your current DMI integrations:

Assess whether your organization would benefit from multiple connectors, especially if you manage multiple Microsoft 365 tenants.

• Update internal documentation and processes:

Ensure your IT and security teams are aware of the new capability and update any relevant procedures.

• Monitor audit logs:

Regularly review audit logs for DMI activity to ensure compliance and detect any unusual behavior.

• No immediate action is required:

If you do not need multiple connectors; your existing integration will continue to function as before.

See Also...

• Engage - Direct Message Injection
• Engage - Direct Message Injection - FAQ