Maybe PF3 has been moved off screen. As it remembers its last screen position you could try moving it using your keyboard immediately after starting it when it 'should' still be Window's main focus. So, start PF3 then immediately use Alt+SPACE, then press the 'M' key and finally try the arrow directional keys on your keyboard to move the PF3 window. You'll have to try all directions because if you don't know where it is you could be moving in the wrong direction. Practice on another window first... perhaps Notepad... so you can see how it works