If your project is still in an .MPP file format, you need to save the file to Project Server and publish it in order to use the Project Server integration. Before loading the file, make sure that you have not saved a custom view as the default for the project as this will cause the Project Server service to hang and prevent the project from being loaded into PM Compass.
To save an .MPP file to Project Server, complete the following steps:
Open the .MPP file in Microsoft Project.
On the Task command tab, click Gantt Chart.
On the Gantt Chart drop-down menu, select a view from the Built-In section, for example, Gantt Chart.
Save the project.
Use Save As and select the Project Web App (PWA) account. If you do not have a PWA account in the Save As dialog box, refer to the Microsoft Project documentation for instructions.
After saving the file to Project Server, you need to publish it. To do this, in Project Server, click File ยป Info then click Publish Project Progress.