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I have downloaded the new Firefox 4 on Mac OS X, getting message that I cannot use this version of Mac OS X and cannot get back open old 3.6.10 format either since it has been replaced. How can I get this to work or replace previous application?

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I have just downloaded Firefox 4 to replace 3.6.10 and am getting a message "You cannot use the application "Firefox" with this version of Mac OS X." How can I fix this or return to the previous version?

I have just downloaded Firefox 4 to replace 3.6.10 and am getting a message "You cannot use the application "Firefox" with this version of Mac OS X." How can I fix this or return to the previous version?

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

For Mac OS X 10.4.11 or Mac OS X 10.5.8 you can look at:

Firefox 3.6.x can be found here: