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Recently when I'm running Firefox (I think usually during downloads) the system will hang, but allows me to close the browser (at least it appears to close -- not showing up as running in the Windows Task Manager).

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But when I try to open Firefox again, I get this error 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. But I can't find any way to close Firefox. Twice, I've tried removing and reloading Firefox, but it's still happening. Any ideas how to deal with this?

But when I try to open Firefox again, I get this error 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. But I can't find any way to close Firefox. Twice, I've tried removing and reloading Firefox, but it's still happening. Any ideas how to deal with this?

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Open the Windows Task Manager > Processes tab and look for firefox.exe.