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Repeatedly getting the - “Firefox is already running, but is not responding" error message....

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  • Last reply by Ed

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Hi I am repeatedly getting the; “Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window” error message following a much earlier [fatal] FF crash. I have tried multiple deletions, Registry clear-outs & re-installs etc.– followed the several different & various "fixes" & suggestions on various forums etc. Have finally found 2 files in the profiles folder >Appdata>Roaming>Mozilla.Firefox>Profiles>*****.default that I can’t get to delete (have managed to remove all other files & folders in this folder thread but these two; “prefs” – a Javascript File “search.json.mozlz4” Mozlz4 file The error message on these 2 files when trying to delete is; “You require permission from Desktop-F71TMLM\”user” to make changes to this file”

I am logged in as Administrator, have checked the “Security” properties on each file and all the settings, permissions etc. appear to be in place supposedly allowing me to make changes/edit/delete each file – but it’s not happening. [And I tried ‘dragging’ them to another folder too – no dice] Suggestions please??

Hi I am repeatedly getting the; “Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window” error message following a much earlier [fatal] FF crash. I have tried multiple deletions, Registry clear-outs & re-installs etc.– followed the several different & various "fixes" & suggestions on various forums etc. Have finally found 2 files in the profiles folder >Appdata>Roaming>Mozilla.Firefox>Profiles>*****.default that I can’t get to delete (have managed to remove all other files & folders in this folder thread but these two; “prefs” – a Javascript File “search.json.mozlz4” Mozlz4 file The error message on these 2 files when trying to delete is; “You require permission from Desktop-F71TMLM\”user” to make changes to this file” I am logged in as Administrator, have checked the “Security” properties on each file and all the settings, permissions etc. appear to be in place supposedly allowing me to make changes/edit/delete each file – but it’s not happening. [And I tried ‘dragging’ them to another folder too – no dice] Suggestions please??

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Before you try again, make sure that no FF processes are running. Close FF > open Task Manager (CTRL-SHFT-ESC) > Processes tab (click the Image name header to sort). If any FF processes exist, R. click and 'End process'.