Issue:   You are unable to edit projects through Project Professional 2010.

In many cases, you may not be able to edit the Projects via Project Professional 2010, if the project has already been checked out.

Resolution:

You can have the user check-in the project; or administrator can forcefully check in the project via PWA.  To forcefully, check in the project via PWA; please follow these steps.

Forcefully check-in the Project follow the below steps.

1.Open the Project Web access site.

2.Under server Setting; select Database Administrator

3.Force Check-in Enterprise Objects.  Select the Project

4.Click to Check In to check in the Projects.