(Updated) Retirement of external access token for actionable messages – moving to Microsoft Entra authentication

Updated May 21, 2026: Phasing out to Legacy Auth Token (EAT) has been initiated and will complete by June 8th 2026. Thank you for your patience. 

[Introduction]

We’re retiring the use of external access tokens for actionable messages and transitioning to Microsoft Entra-based authentication. This update enhances security and aligns with modern identity standards, providing a more robust and compliant experience for actionable messages.

[When this will happen]

This change takes effect on May 15, 2026. After this date, external access tokens will no longer be supported.

[How this affects your organization]

Who is affected:

Organizations using actionable messages that currently rely on external access tokens.

What will happen:

• Actionable messages that depend on external access tokens will fail after May 15, 2026.
• All integrations and workflows using actionable messages must adopt Microsoft Entra authentication.
• This change improves security posture by leveraging Entra’s identity and access management capabilities.

[What you can do to prepare]

• Review all actionable message implementations in your organization.
• Update integrations to use Microsoft Entra authentication before May 15, 2026.

Learn more:

• Actionable messages in Outlook and Office 365 Groups
• Enable Entra token for Actionable messages

[Compliance considerations]

No compliance considerations identified, review as appropriate for your organization.