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Firefox cannot start because a process is already running

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  • Last reply by cor-el
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Bozidar Simonovic
Bozidar Simonovic

Firefox cannot start because Mozilla process is already running and I cannot stop it.

I tried to restart my PC but no success. I reinstalled Mozilla/Firefox but again error message appears:

"Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

Firefox cannot start because Mozilla process is already running and I cannot stop it. I tried to restart my PC but no success. I reinstalled Mozilla/Firefox but again error message appears: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

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cor-el
cor-el
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  • Top 10 Contributor

You can check this support article.

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