Recently I upgraded to the latest version - when I shut down Firefox, the interface shuts down, but firefox.exe stays active. I try to start a new Firefox session and a message comes up saying that Firefox is still running and must be shut down or I must reboot before a new session can start. I try to shut down firefox.exe via the Task Manager but it will not shut down, so I have to reboot. I tried re installing, but same problem remains.