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Firefox 4.0 will not install. I have Mac OSX 10.4.11. Error message 10661.

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  • Last reply by cor-el

Lloyd Frohreich
Lloyd Frohreich
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I tried to install Firefox 4.0 and I got an error message 10661 and it said my system would not support it. I have Mac laptop with MAC OSX 10.4.11. Why won't it install using this operating system?

I tried to install Firefox 4.0 and I got an error message 10661 and it said my system would not support it. I have Mac laptop with MAC OSX 10.4.11. Why won't it install using this operating system?

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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Firefox 4 doesn't run on a PowerPC Mac.

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: