Whenever I have itunes or even a quicktime video file open on my desktop (Win 7 64bit), Firefox (v.48.0.2) will not launch. If I close iTunes or the quicktime file, then it will launch and then I have to re-launch the other applications again. Can't figure out why Firefox does this. This has been happening for over a year and I'm finally getting frustrated enough to post and ask why. It's a hassle when you are viewing a quicktime movie, a tutorial for example, then need to check something out online, Firefox just will not launch unless the quicktime video is closed first, why is that? I can repeat this issue consistently.