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Firefox won't start, it thinks it's already running but isn't

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When I try to start Firefox I get a message saying it's already running but not responding and telling me :"To open a new window, you must first close the existing Firefox process, or restart your system." Since it's not running and task manager does not show a running process I obviously can't do that. I have restarted my system several times, all with the same result. I have even tried uninstalling Firefox, downloading it from scratch and installing it again - but the result is still the same.

When I try to start Firefox I get a message saying it's already running but not responding and telling me :"To open a new window, you must first close the existing Firefox process, or restart your system." Since it's not running and task manager does not show a running process I obviously can't do that. I have restarted my system several times, all with the same result. I have even tried uninstalling Firefox, downloading it from scratch and installing it again - but the result is still the same.

Chosen solution

Yes. If there isn't a default profile then you need to create a new profile or delete the profiles.ini file to make Firefox create a new default profile as you appear to still have that file currently to get that error.

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All Replies (4)

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Hi,

I have followed the instructions and the folder Russell/AppData/Roaming/Mozilla/Firefox/Profiles is completely empty so there's no default profile for me to edit, but I still get the same error message each time I try to start Firefox. Do I need to somehow create a default profile?

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Chosen Solution

Yes. If there isn't a default profile then you need to create a new profile or delete the profiles.ini file to make Firefox create a new default profile as you appear to still have that file currently to get that error.

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Thank you so much. I deleted the profiles.ini file and it fixed the problem!