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Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

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  • Last reply by Matt_G

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Every time I go to open Firefox I get this message: Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

Every time I go to open Firefox I get this message: Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

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Hi archermjones,

Have you looked at the Knowledge Base article "Firefox is already running but is not responding" error - How to fix? There is a lot of good troubleshooting information in the article.

Hopefully this helps!