Sorry to hear about this problem. When Firefox doesn't appear after 10 seconds, could you check the Windows 10 Task Manager to see whether it is listed there? To call up the Windows 10 Task Manager, you can press Ctrl+Shift+Esc The Task Manager has numerous tabs. The first one to check is called Processes, and Firefox may appear under Firefox or under the program name firefox.exe. Anything? You also can check the Details tab, it would be under firefox.exe. Does Firefox seem to be stalled there -- memory use has stopped growing and its CPU usage is 0%? Or is Firefox completely missing?