As you work on a project by using a SharePoint task list, you may find that the project becomes more complex, and could really use the added functionality offered by Project Web App. For example, you may decide that you’d like to capture timesheet data, or put in place a workflow that allows for manager approval as the project’s tasks progress. If the SharePoint task list is already visible in Project Web App, the Project Server administrator can easily switch the project from being an editable SharePoint task list that is displayed in Project Web App, to being an editable project in Project Web App that is displayed as a SharePoint task list.
To make a viewable SharePoint task list into an editable project in Project Web App:
In Project Web App, click Settings, and then click PWA Settings.
In the Operational Policies section, click Connected SharePoint Sites.
In the Enterprise Project Features column, for the row that contains your project, click Activate.
Note: If the button in the Enterprise Project Features column says Deactivate, the SharePoint task list is already set up as an enterprise project. You should also see a green Active indicator next to the button.
Click OK on the dialog box that appears to set the selected SharePoint task list to read-only, and allow edits to the project from within Project Web App.