If you see this, it means the application you’re working in has crashed. Sometimes you can try the “Wait for the program to respond” button and it may come back. Clicking on “Close the program” often doesn’t do much.
To fix this, right-click anywhere on the taskbar along the bottom and then click “Task Manager”
Highlight the problem application and click “End Task” in the bottom right-hand corner of the Task Manager.
Alternatively, you can right-click on the problem application and choose “End task”