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When I downloaded the new Firefox 4 and tried to run it, it says "You cannot use the application "Firefox" with this version of Mac OS X. What should I do?

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  • Last reply by cor-el

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I like running firefox over safari, on my Macbook (which is 4 years old), but firefox just prompted me to upgrade to Firefox 4 so I did it, but then when I tried to open Firefox is says, "You cannot use the application "Firefox" with this version of Mac OS X." What should I do? Should I downgrade to Firefox 3.6? The Mozilla firefox 3.6 download page says this, "Firefox 3.6.x will be maintained with security and stability updates for a short amount of time. All users are strongly encouraged to upgrade to Firefox 4"

I like running firefox over safari, on my Macbook (which is 4 years old), but firefox just prompted me to upgrade to Firefox 4 so I did it, but then when I tried to open Firefox is says, "You cannot use the application "Firefox" with this version of Mac OS X." What should I do? Should I downgrade to Firefox 3.6? The Mozilla firefox 3.6 download page says this, "Firefox 3.6.x will be maintained with security and stability updates for a short amount of time. All users are strongly encouraged to upgrade to Firefox 4"

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Firefox 4 requires at least OS X 10.5 and an Intel Mac.

For a version that runs on Mac OS X 10.4.11 or Mac OS X 10.5.8 you can look at:

Firefox 3.6.x (Mac OS X 10.4 and later) can be found here:

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Thanks for the reply so quickly! Is the tenfourfox going to be be just as safe and as high of quality as the Firefox 4? Also since Mozilla's website says, "Firefox 3.6.x will be maintained with security and stability updates for a short amount of time. All users are strongly encouraged to upgrade to Firefox 4" does that mean if I go back to 3.6 there will be security and stability issues after a "short amount of time"?

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Tenfourfox is a development independent of Mozilla, so anything that Mozilla says doesn't apply the that version. Tenfourfox uses code from the official Mozilla version AFAIK and makes sure that if works on those older Mac OS X versions that aren't supported by Mozilla. It is a way to continue using Firefox if you can't update your OS.