As of June 8, 2026, Microsoft no longer supports legacy EAT authentication for Outlook Actionable Messages. Migrate the provider to Microsoft Entra ID token authentication, then validate the token, card, and action endpoint separately with authorized test recipients. This Outlook Actionable Messages 2026 authentication migration test is for teams testing their own service, not registering accounts on third-party services.
This week’s action: inventory the existing authentication and provider registration, then create a controlled baseline before changing the integration.
This guide is for developers migrating an existing Actionable Messages provider, QA engineers distinguishing delivery from interaction failures, and Microsoft 365 environment owners planning authorized test recipients.
Last updated October 25, 2026. The migration date and support status are checked against Microsoft’s Entra ID token migration guidance.
Start with the retired path, not the visible symptom
Microsoft confirms that the migration from EAT to Microsoft Entra ID token authentication was completed on June 8, 2026, and that the old authentication method is no longer supported. Treat a failure after that date as a possible authentication migration issue, but do not assume it explains every symptom. Check the authentication method in the provider integration and compare it with the current Microsoft guidance.
Then split the report into observable outcomes:
- No email received: investigate sending, recipient address, filtering, and delivery evidence.
- Email received, card absent: investigate recipient eligibility, provider registration, message content, and client support.
- Card visible, action fails: inspect the request path, endpoint response, and server-side authorization.
- Request reaches the endpoint, but no expected operation occurs: review token validation and the application’s business rules separately.
Those are different failure layers. A delivered message does not prove that a card can render, and a rendered card does not prove that the endpoint accepted an authenticated request. Keeping these results separate prevents an address change or a resend from masking an integration defect.
For mail-arrival evidence, use a controlled test that records whether the message reached its intended test inbox. The mail arrival troubleshooting guide can help frame that check, but it cannot establish that a recipient meets Microsoft 365 test-user requirements.
Before changing configuration, preserve a rollback baseline
First map the existing integration. Record the provider registration, action URL, sending identity, current authentication type, token-handling logic, and the service operation triggered by each action. Mark which items are owned by the team and which depend on Microsoft 365 configuration or client behavior. Store the current configuration securely; do not copy secrets into a test report or email sample.
Next, separate the migration environment from production. Use a controlled environment, an authorized Microsoft 365 test recipient, and test data that does not contain real customer information. Do not assume a temporary inbox is an organizational test mailbox or that it qualifies for a provider’s test scope. Recipient eligibility and approval depend on the registration scope and current Microsoft instructions.
Before the migration, capture a known-good or known-failing baseline. Save the message source or an appropriately sanitized sample, timestamps from the sending system, the visible card result, the action request log, and the endpoint’s validation outcome. Redact tokens, personal information, and any other sensitive values. If a message has to be shared across the team, preserve the evidence needed to reproduce the issue without distributing credentials.
There are several easy-to-miss costs in this stage. A shared company inbox can mix test messages with operational mail. Reusing a personal address can expose real identifiers in logs and screenshots. Changing the recipient, template, and authentication configuration at once can make the result impossible to interpret. A test inbox can show that a message arrived, but it cannot prove provider eligibility, correct token validation, or production deliverability.
Move the provider registration to Entra ID
Follow Microsoft’s current migration instructions for the provider rather than treating this as a mail-template-only change. The migration requires the integration to use Microsoft Entra ID token authentication and the provider registration to carry the corresponding authentication information. Microsoft’s migration instructions are the reference for the current configuration process.
At a high level, the team should:
- Register and configure the application according to the current Microsoft procedure.
- Set the required application identity and API permissions for the integration.
- Update the Actionable Messages provider registration with the matching authentication information.
- Confirm that the registered action URL and the service endpoint align with the environment being tested.
- Recheck the sending identity and recipient scope before sending a test message.
Do not copy configuration values from a different provider or environment without confirming their purpose. An application identifier, a permission assignment, and a provider registration are related, but they are not interchangeable. A mismatch can leave the email delivery path apparently healthy while the card or action path fails.
The registration scope matters. Microsoft documents registration and testing scopes that can include test-user, organization, and broader availability paths, with scope-specific requirements and approvals. The applicable route is determined by the current official instructions and the team’s authorization—not by the kind of inbox used to receive a message. Use the Actionable Message Developer Dashboard guidance to review provider registration and the supported testing process. Do not treat a temporary address as a substitute for an eligible organizational test user.
Validate the token before trusting the button
Test the action endpoint independently from the message display. A card can be rendered even when its button has not yet produced a valid request. Conversely, a request can reach a server while still failing authentication or authorization. The endpoint is the security boundary: it must decide whether the request is legitimate before performing the requested operation.
For a controlled request, verify the token according to Microsoft’s current requirements. The Microsoft access-token validation documentation explains why a resource must validate a token intended for it and how token claims apply. Use the Actionable Messages security requirements alongside that guidance; do not invent a shortcut based on the presence of a bearer token or a successful HTTP connection.
Keep these outcomes distinct in test logs:
- The request did not reach the endpoint.
- The endpoint received a request but rejected its token.
- The token was acceptable, but the caller lacked the required permission.
- Authentication and authorization passed, but a business rule rejected the operation.
- The request passed all checks and produced the intended result.
For each outcome, preserve a sanitized request identifier, the validation decision, the response status, and the resulting application state. Avoid storing raw tokens in logs or test artifacts. If a token is invalid, expired, intended for another resource, or otherwise unsuitable, the endpoint should not perform the protected action. The exact checks must follow the current token format and official requirements; the test should confirm the service’s implementation rather than assume a particular claim layout.
A strong negative test is as important as a successful action. Exercise an invalid-token case, a permission mismatch, and a validly authenticated request that is rejected by business logic. These cases show whether the service distinguishes authentication from authorization and application behavior. A button appearing in the client, or an HTTP request appearing in a log, proves neither.
Send the message and read the results by layer
Once provider configuration and endpoint checks are ready, send a message generated by the team’s own service to an authorized recipient that matches the current registration scope. Use a controlled test action with a predictable, reversible effect. Do not test against real customer data or perform an irreversible operation simply to prove that a button works.
Record each stage independently:
- Delivery: Did the message reach the authorized recipient?
- Rendering: Did the expected Actionable Message card appear?
- Interaction: Was the button available and did it initiate the expected request?
- Endpoint security: Did the server accept or reject the request for the intended reason?
- Business result: Did the accepted action change only the expected test state?
If the email arrives but the card is missing, check the recipient’s eligibility for the registration scope, provider-registration status, message construction, and client support. Do not start by blaming the address. If the card appears but the request fails, use endpoint logs to distinguish a transport problem from a token or permission rejection. If the endpoint accepts the action but the expected state does not change, investigate the application’s business logic and test data.
A message in a test inbox can support the delivery part of this record. It cannot establish the full Microsoft 365 recipient scope, prove the card will render in every client, or verify the server’s security checks. For separating test traffic from personal mail, the privacy-path options guide can help compare approaches. Choose a mailbox only when it is permitted for the test and does not stand in for an organizational identity requirement.
Use decision branches to choose the next test
- If the integration still uses EAT, migrate the provider to Microsoft Entra ID token authentication before treating the old flow as a supported baseline. If the authentication method is unclear, inspect provider configuration and application logs first.
- If the recipient is not authorized for the configured test scope, stop the rendering test and arrange an eligible Microsoft 365 recipient under the current registration rules. Do not substitute an unrelated temporary address.
- If delivery fails, investigate the sending and receiving path before changing card code. If delivery succeeds but the card does not render, move to eligibility, registration, message, and client checks.
- If the card renders but the action is rejected, inspect the endpoint’s token-validation and authorization results. If those pass, check the business rule and test state.
- If the endpoint succeeds but the client does not show the expected result, compare the server-side state with the client behavior and preserve both observations; do not label the whole flow successful based on one side.
This branch-based approach keeps the next action tied to evidence. It also helps QA report a precise defect rather than an ambiguous “email test failed.”
Compare migration evidence before expanding access
The first table is a compact acceptance record. It distinguishes what a test can establish from what it cannot.
| Checkpoint | Evidence to retain | What it establishes | What it does not establish |
|---|---|---|---|
| Provider configuration | Sanitized configuration version and registration scope | Which authentication setup was tested | That every recipient or client is eligible |
| Email delivery | Recipient-side arrival and sending-system record | That this message reached this test recipient | That the card rendered or the endpoint is secure |
| Card rendering | Sanitized message sample and client observation | That the card appeared in this test context | That a button request passed server validation |
| Token validation | Endpoint decision and relevant sanitized logs | How the service handled the controlled request | That unrelated requests or environments are safe |
| Business operation | Test-state before and after the request | Whether the permitted action had the intended effect | That production behavior is guaranteed |
The second table compares test routes. The right choice depends on what the team needs to prove.
| Test route | Best used to verify | Main limitation | Decision |
|---|---|---|---|
| Authorized Microsoft 365 test recipient | Recipient eligibility, card rendering, and the integrated action flow | Requires an appropriate organizational test setup and scope | Use for end-to-end acceptance |
| Isolated endpoint request | Token handling, permissions, rejection paths, and business rules | Does not prove email delivery or client rendering | Use before and alongside mail tests |
| Separate temporary receiving address, where permitted | Receipt of non-sensitive test mail outside an organizational eligibility check | Does not replace a qualified Microsoft 365 recipient or prove action security | Use only as auxiliary evidence |
After the controlled end-to-end case passes, expand the rollout under the team’s normal approval process. Before widening access, review the provider registration, application permissions, sending identity, and action URL again. Keep a versioned configuration record and sanitized test evidence so the team can identify which setup was accepted.
A passing test is evidence about the tested environment and recipient. It is not a general guarantee of production delivery, universal client rendering, or security for every request. Record those limits in the acceptance note. If any component changes after approval—especially registration scope, permissions, endpoint behavior, or token validation—rerun the affected checks before relying on the earlier result.
FAQ: migration and acceptance
What should change first after EAT authentication stops working?
Identify the authentication method in the provider integration, then plan the move to Microsoft Entra ID token authentication. Capture separate results for delivery, card rendering, button behavior, and endpoint decisions before editing the configuration. That baseline shows which layer changes after migration and avoids treating a successful email arrival as proof that the new authentication flow works.
How should Entra ID authentication be tested with test users?
Use an authorized Microsoft 365 test recipient that fits the provider registration’s permitted scope. Follow the current Microsoft instructions for registration and approval, then test a controlled action against the team’s endpoint. Confirm the service validates the token for the intended resource and permits only the authorized operation. A visible card is not a substitute for server-side validation evidence.
Why might an Actionable Message arrive without its card?
Arrival confirms only that the email reached the recipient. Check whether the recipient is eligible under the configured testing scope, whether the provider registration is correct and active, and whether the client supports the message and action. Preserve the message and registration details before changing the address; a new recipient will not fix an invalid registration or unsupported client behavior.
What proves that a button request passed server-side validation?
Use the endpoint’s validation and authorization results, not the button display or the fact that a request was sent. Test invalid-token, permission-mismatch, and business-rejection cases separately from an authorized successful action. The evidence should show why the server accepted or rejected the request and whether the expected test state changed only after a permitted action.
Keep the inbox test separate from identity proof
For this migration, the qualified Microsoft 365 recipient and the protected action endpoint are the decisive parts of acceptance. A separate temporary inbox can be considered only for an authorized, non-sensitive mail check where organizational eligibility is not being tested. It cannot replace Microsoft’s provider registration, recipient-scope requirements, or server-side token validation.
If that auxiliary mail check fits the workflow, review BoxTmp’s current receiving options before using it and confirm that the address is appropriate for the test. Keep the acceptance record explicit: inbox evidence may show that a message arrived, while the Microsoft 365 test recipient, rendered card, validated request, and expected endpoint result must each be verified on their own.
Frequently asked questions
What should I change first after EAT authentication stops working?
First identify which authentication method the provider integration actually uses, then plan the migration to Microsoft Entra ID token authentication. Record mail delivery, card rendering, button behavior, and endpoint responses as separate results before changing configuration. That baseline helps locate the failing layer and gives the team a safe comparison when it retests the updated provider registration.
How can I test Entra ID token authentication with test users?
Use an authorized Microsoft 365 test recipient that matches the scope allowed by the provider registration. Follow the current Microsoft registration and approval instructions for that scope, then exercise the action endpoint with a controlled request. Check that the service validates the token’s applicable claims and only performs the intended operation for an authorized request; a visible card alone is not proof.
Why can an Actionable Message arrive without showing its card?
Email delivery and card rendering are separate outcomes. If the message arrives but the card does not render, check whether the recipient is eligible for the configured test scope, whether the provider registration is active and correct, and whether the client supports the message and action. Preserve the received message and registration details before changing the address or resending.
How do I know whether a button request passed server-side validation?
Do not infer successful authentication from a button being visible or an HTTP request being sent. Inspect server-side validation results for the controlled request, including the token’s applicability to the service and the authorization decision. Then confirm that only a valid, permitted request triggers the expected business action. Keep invalid-token, permission-mismatch, and business-rejection outcomes distinct in test evidence.
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