Why does it display “Firefox is already running”?

Asked By 10 points N/A Posted on -

When I close firefox and then restart it why does it display "Firefox is already running"?

Best Answer by JayaB
Answered By 0 points N/A #92946

Why does it display “Firefox is already running”?



Hello Isabella.

After you close Firefox, it usually takes some time before the process totally stops.  You can verify it by viewing the active processes in Task Manager.  If you double-click the Firefox shortcut and Windows attempts to launch while the previous Firefox process is still running (or in the process of shutting down) then "Firefox is already running" is the error message that you will get.  Delays in shutting down could be due to high processor activity, high hard drive activity or a faulty Firefox plug-in that would not shut down properly/

If this happens often then you could try the following:

1.  Wait for a few seconds (5 or 10) before trying to open a new instance of Firefox after you have just turned off a previous session.  Wait longer if you there are several simultaneously running processes that are taking up CPU time or causing high hard disk activity.

2.  If it takes too long for the previous process to close, try disabling add-ins.


Best Answer
Best Answer
Answered By 0 points N/A #92947

Why does it display “Firefox is already running”?


Hi Isabella,

I have encountered the same problem  number of times. The reason can be one of the following.

1) When multiple tabs are opened, content in one of the tab may take longer to load or may hang, inturn causing the firefox  to freeze. When we try to close the browser and reopen it , ' Firefox already running'  problem may be encountered.

2) This can also happen when someone turns your computer off while Firefox is still running.

2) This pop up may appear when  tried to open new window after Firefox quit abruptly due to slower application response.

When you get this error message saying ' Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system'   try this:

 – Open Task Manager (Shortcut :Press Ctrl + Alt+ Delete) , Goto Processes tab , Select Firefox.exe . Click on End Process button. This should kill the Firefox process currently running. Now restart Firefox.

* Note : 'Show processes from all users' checkbox needs to be clicked on Windows task manager page *

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