Power BI Error:
AADSTS90009

What does this error mean?

An application requested a token for itself, but didn't use its GUID-based application ID as the resource identifier.

Common causes

• 1The resource parameter in the token request uses an App ID URI (e.g. api://contoso) instead of the application's GUID-based Application (client) ID
• 2Client ID and resource ID in the OAuth request reference the same app, but the resource is specified in a non-GUID format
• 3Custom service-to-self token flow where the app authenticates against itself for internal API calls without using its GUID identifier
• 4Misconfigured on-behalf-of (OBO) or client credentials flow where the requesting app and target resource collapse to the same registration
• 5Legacy code paths still using ADAL patterns where the resource was a URI, now broken under MSAL/v2.0 endpoints requiring GUID-based self-token requests

How to fix it

1. 1Open the failing token request and replace the `resource` (or `scope`) value with the application's GUID-based Application (client) ID — find this in Entra ID > App registrations > Overview > 'Application (client) ID'
2. 2If you're on the v2.0 endpoint with MSAL, request the scope as `<app-guid>/.default` instead of an App ID URI like `api://<app>/.default`
3. 3Audit whether the app actually needs to request a token for itself — in most service-to-service flows the resource should be a different downstream API, not the same registration; if so, fix the resource ID to point at the correct target
4. 4For Power BI embedded or custom Fabric apps using OBO, confirm the middle-tier app and the resource app are genuinely the same registration; if they are, switch the resource to the GUID, otherwise split into two registrations
5. 5Re-run the auth flow and capture the full token request in Fiddler or the Entra ID sign-in logs to verify the resource parameter is now the GUID and the request returns 200

Frequently asked questions

Other authentication errors