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Updated to Firefox 4.0, now I can't open the browser.

Motorman1959
Motorman1959
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I'm running a Mac OS X Version 10.4.11 Just updated to Firefox 4.0 after Yahoo advised that things would run better. Upgraded from Firefox 3.1.16 (I think).......now I cannot open the Firefox browser at all....it won't let me launch the browser. It says: "You cannot open the application "Firefox" because it is not supported on this system". How do I go back to the old version?.....at least I was able to launch it and use it? Any help would be appreciated. Posted: Fri 06May2011

I'm running a Mac OS X Version 10.4.11 Just updated to Firefox 4.0 after Yahoo advised that things would run better. Upgraded from Firefox 3.1.16 (I think).......now I cannot open the Firefox browser at all....it won't let me launch the browser. It says: "You cannot open the application "Firefox" because it is not supported on this system". How do I go back to the old version?.....at least I was able to launch it and use it? Any help would be appreciated. Posted: Fri 06May2011

All Replies (1)

Matt Brubeck
Matt Brubeck
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Sorry, Firefox 4 is not compatible with Mac OS X 10.4. You can download and reinstall the previous version (Firefox 3.6) from here: http://www.firefox.com/all-older.html

Or, if you have a PowerPC Mac, you can try this unofficial version of Firefox: http://www.floodgap.com/software/tenfourfox/