Firefox would not open when I booted my computer this morning. I got an error message that said: Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window. I have tried everything I can think of but, nothing is working. I have opened the profile as instructed and tried to delete the parent.lock file but, it would not delete because it tells me it is in use in firefox. I have opened the task manager and there is nothing running. I also uninstalled firefox and downloaded it again but, that did not help either. I don't know what to do now. Does anyone have any other suggestions?