This tool allows you to open a project from your working area without opening the Project Browser.
The File > Open menu lists the names of projects in your Working Projects area ordered by their modified date. Any project from this list can be opened by clicking on it. The list may not display all the projects in your Working Projects area, as the maximum number listed is set in History Lists from Impact Options - Database Operation.
If you have no projects in your working area, the Working Projects list will not be displayed in the menu.
Use the Refresh tool to update the list (this is updated automatically when you open/update projects, but another user may have assigned a project to you).