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Firefox refuses to start, saying that it's already running, must restart window in the end.

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This error message shows up: "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."

This error message shows up: "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."

Chosen solution

Please upgrade your browser to Firefox 8 and check

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Chosen Solution

Please upgrade your browser to Firefox 8 and check