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I have a Mac running OS 10.5.8. I downloaded Firefox 4 and not the program will not open at all. I am also unable to download the previous version that was running fine. I'm using Safari to contact you.

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  • Last reply by cor-el

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I have a Mac G5 running OS 10.5.8. I downloaded Firefox 4 and now the program will not open at all. I get an error message that reads --

"You cannot open the application "Firefox" because it is not supported on this architecture."

I am also unable to find a link to download the previous version that was already running fine. (I'm using Safari to contact you.)

I have a Mac G5 running OS 10.5.8. I downloaded Firefox 4 and now the program will not open at all. I get an error message that reads -- "You cannot open the application "Firefox" because it is not supported on this architecture." I am also unable to find a link to download the previous version that was already running fine. (I'm using Safari to contact you.)

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http://www.mozilla.com/en-US/firefox/4.0/system-requirements/

Mac Operating Systems

  • Mac OS X 10.5
  • Mac OS X 10.6

Recommended Hardware

  • Macintosh computer with an Intel x86 processor
  • 512 MB of RAM
  • 200 MB hard drive space
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OK, I think it's the Intel processor that's the culprit. My G5 is an older Power PC (pre-Intel). So how then can I restore Firefox 3.6? I can't seem to find any download links.

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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: