OS: windows 7 32 and 64-bit Symptom: firefox can be open can close "properly" without error message. But when you look in the task list, firefox is still there. You still can open firefox without problem. It will add another process if you close it. So more and more processes in the task list if you repeating open and close after surfing some web sites. You cannot kill the task, even you are administrator. The only way to get rid of it is to re-start the PC. It happens in 3 of my PCs.