Unable to list users from a different Okta org using OAuth 2.0 Authorization Code Flow

Questions OAuth/OIDC
1

I have created an OAuth app in my Okta account and shared the client ID and secret with the client (admin) from another Okta organization. The admin is trying to authenticate, but they receive an error message: 'Unable to sign in

I have checked the Okta OAuth app’s redirect URIs, client ID, and client secret. I also verified that the scopes (e.g., okta.users.read) are configured correctly. The app works when assigned to users in my organization, but when the client (from another Okta org) tries to authenticate, it fails.

Can anyone guide me on what I need to configure to allow external Okta organizations to authenticate successfully using OAuth 2.0? Do I need to assign users from the client’s Okta org to my app, or is there another configuration needed?

2

You can check the system logs to see what this error is really about: View Organization activity with the System Log based on the client ID—you would get more information about the issue there.

Also, it’s better this can be a support ticket in the Okta portal, as this requires much more information about how the admin is accessing and what the requirements are and the scope they are requesting.