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How do I undo a Firefox upgrade that went onto my computer but is incompatible and is now preventing me from accessing the Web?

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  • Last reply by cor-el

ABerghoff
ABerghoff
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Hello. Please help! I just upgraded from Firefox 3.6.22 to Firefox 4.0 on my Mac PowerBook G4 laptop. I run Mac OS X Tiger 10.4. I did not know that Firefox 4.0 would go onto my computer if it was not compatible. It downloaded and replaced the old version. When I went to open up Firefox, it told me it could not open because the system was incompatible. Now I cannot access the Internet using Firefox, which I prefer to other browsers. How can I go back to my old version of Firefox?

Thank you.

Hello. Please help! I just upgraded from Firefox 3.6.22 to Firefox 4.0 on my Mac PowerBook G4 laptop. I run Mac OS X Tiger 10.4. I did not know that Firefox 4.0 would go onto my computer if it was not compatible. It downloaded and replaced the old version. When I went to open up Firefox, it told me it could not open because the system was incompatible. Now I cannot access the Internet using Firefox, which I prefer to other browsers. How can I go back to my old version of Firefox? Thank you.

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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Firefox 4 versions and later do not run on a PowerPC Mac.

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

For an unofficial Firefox 6 compatible version (TenFourFox) that runs on PowerPC Macs with OS X 10.4.11 or OS X 10.5.8 you can look at:

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