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Widespread "Firefox is already running" problem suggests it is not closing properly - is Mozilla fixing this?

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Several people including me have reported a problem when closing Firefox and then attempting to re-open it. The message "FF is already running and must be closed...." appears, yet the taskbar does not show an active FF. At that point it is necessary to use Task Manager to close the old run. 1. This did not always happen on my computer- has started recently. 2. Most of the time it is in fact possible to open multiple versions of FF without difficulty. This problem only seems to happen if I close the first session and then immediately try to open a new one. So my question is what causes this, not what workaround can to used when it occurs.

Several people including me have reported a problem when closing Firefox and then attempting to re-open it. The message "FF is already running and must be closed...." appears, yet the taskbar does not show an active FF. At that point it is necessary to use Task Manager to close the old run. 1. This did not always happen on my computer- has started recently. 2. Most of the time it is in fact possible to open multiple versions of FF without difficulty. This problem only seems to happen if I close the first session and then immediately try to open a new one. So my question is what causes this, not what workaround can to used when it occurs.

Chosen solution

1- Both of those problems(ending Firefox and restarting) are answered in

http://dmcritchie.mvps.org/firefox/firefox-problems.htm#close_firefox

2- Multiple versions of Firefox requires you to use -no-remote on your non default browser/profile combination. Which can't be by accident so either you messed up in start parameters or you never did have multiple versions of firefox running at the same time.


Please mark "Solved" one answer that will best help others with a similar problem -- hope this was it.

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Chosen Solution

1- Both of those problems(ending Firefox and restarting) are answered in

http://dmcritchie.mvps.org/firefox/firefox-problems.htm#close_firefox

2- Multiple versions of Firefox requires you to use -no-remote on your non default browser/profile combination. Which can't be by accident so either you messed up in start parameters or you never did have multiple versions of firefox running at the same time.


Please mark "Solved" one answer that will best help others with a similar problem -- hope this was it.