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Firefox in Windows 10 will not execute.

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peter.jcarbajal
peter.jcarbajal

On my pc, Mozilla Firefox continuously loops the error message, “Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window.” It then proceeds to close and loop this error. I have uninstalled and reinstalled multiple times, as well as did a “refresh” in deleting all my extensions and addons upon the new installation. Please advise. Thank you.

On my pc, Mozilla Firefox continuously loops the error message, “Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window.” It then proceeds to close and loop this error. I have uninstalled and reinstalled multiple times, as well as did a “refresh” in deleting all my extensions and addons upon the new installation. Please advise. Thank you.

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Kiki
Kiki
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Mozilla Staff

Hi Peter,

You may want to check out "Firefox is already running but is not responding" error - How to fix. Feel free to let us know if that doesn't solve your issue.

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