I often get this message. Firefox is already running but is not responding.To open a new window you must first close the excisting Firefox process or restart your system.Thankyou Colin.
So this message appears mainly if I were changing web sites.Can't carry on until I have cleared everything from screen,gone on to my Thunderbird e-mail then Firefox will load again.I can then just carry on till next time.
ప్రత్యుత్తరాలన్నీ (1)
Please look at "Firefox is already running but is not responding" error - How to fix
The initial problem is solved by killing any process firefox.exe, ( & maybe also plugincontainer.exe) Make sure you always close firefox by using the option Firefox Button -> Exit
You may need to investigate further and clear some of the duplicated files that may exist.