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Firefox says my operating system doesn't support upgrade. I have MAC OS X 10.5.6

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  • 34 have this problem
  • 1043 views
  • Last reply by cor-el

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When I tried to download the latest Firefox version, a message said that my operating system doesn't support the upgrade. But the information on download page says MAC OS X 10.5 or better is okay. My system is MAC OS X 10.5.6

Chosen solution

Do you have a Intel processor or a PowerPC processor as your user agent suggests and Mach-O would indicate an even older OS X version than 10.5 (possibly OS X 9).

  • Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3

Are running Firefox in some compatibility mode via Rosette?

See:


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Chosen Solution

Do you have a Intel processor or a PowerPC processor as your user agent suggests and Mach-O would indicate an even older OS X version than 10.5 (possibly OS X 9).

  • Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3

Are running Firefox in some compatibility mode via Rosette?

See:


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Thanks for your response--now I understand. Yes, my Mac is an older PowerPC Mac. I've upgraded Firefox to 3.6.20 and it's working fine. Not gonna buy a new Mac in this economy, ya know? I appreciate your help. Aloha from Hawaii.

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You're welcome

For an unofficial Firefox 4 compatible version (TenFourFox) that runs on PowerPC Macs with OS X 10.4.11 or OS X 10.5.8 you can look at: