Hi Ismail, it typically points to missing configurations, module incompatibility, or security issues.
1. Make sure you’re using the latest version of the UnitTesting module compatible with Mendix 10.24.0. Older versions may not support recent platform changes.
2. Ensure that your "Demo_Admin" user role used for testing purposes when demo users are enabled in your app. Even though it’s called “Admin,” it doesn’t automatically have full access to everything. Permissions depend on how it's mapped to module roles.
3. The test runner may attempt to create or read objects like UnitTestSuite, UnitTestCase or UnitTestResult.
4. Ensure proper entity access is configured in security for the user role you're using to run the tests.
5. If your test cases include custom logic. Make sure no restricted resources are accessed without proper permission. You are not referencing deleted or outdated module elements
6. Sometimes the high-level message masks a specific underlying error (e.g., null reference, missing object, unauthorized access).
I hope this one helps you! :)