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I receive messages that say Firefox is already running and I have to close the old version. How do I do this?

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What do I do when I seem to have an older version and a new version of Firefox on my computer? I receive a message: "Firefox is already running. You have to close the older version." How do I do this? Please help. [email removed from public]

What do I do when I seem to have an older version and a new version of Firefox on my computer? I receive a message: "Firefox is already running. You have to close the older version." How do I do this? Please help. [email removed from public]

Modified by James

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Hello, on Windows 7, you can check for and terminate hidden applications using the Task Manager -- Ctrl+Shift+Esc

Of course, be careful not to terminate any program where you have unsaved data or transactions in process.

Does the "Processes" tab show any "firefox.exe" processes running that do not appear on screen?

If not, it could be a problem with a local file.