Views:
Applies to Product - Power Apps

What’s happening?
Unable to install the "Microsoft Project Service Core" app in a new environment in a model-driven app.

Reason:
This of being unable to install the "Microsoft Project Service Core" app can occur if the environment was created with the "Enable Dynamics 365 apps" option set to "Yes." This setting makes the instance a CRM instance, which does not support the installation of the Microsoft Project Service Core app.

Resolution:
To resolve this, create a new environment without enabling Dynamics 365 apps. Follow the steps mentioned in this article Deploying Project for the web - Project for the web | Microsoft Learn for creating a new environment to install the Microsoft Project Service Core app. If specific errors such as "Object reference not set to an instance of an object" occur, run diagnostic queries and mitigation scripts as detailed in the documents. For intermittent issues, try manually redeploying the app.