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AFTER downloading Firefox 4.0 I get a "system does not support" message and nothing happens. My old Firefox has been replaced by this one that dosn't work.

RCCSCA
RCCSCA
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Asked by Firefox to download Firefox 4.0 for OSX I did so. It replaced my old Firefox that worked fine. When I try to open it I get a Firefox "cannot be launched" window and nothing more happens. I tried to redownload Firefox 3.616 but to open it I get a "choose an application" message and I don't know which application to use.

Asked by Firefox to download Firefox 4.0 for OSX I did so. It replaced my old Firefox that worked fine. When I try to open it I get a Firefox "cannot be launched" window and nothing more happens. I tried to redownload Firefox 3.616 but to open it I get a "choose an application" message and I don't know which application to use.

Chosen solution

You can get an unofficial version of Firefox 4 that runs on Mac OS X 10.4 from http://www.floodgap.com/software/tenfourfox/

Or you can re-download Firefox 3.6 from http://www.mozilla.com/en-US/firefox/all-older.html

Read this answer in context 👍 15

All Replies (4)

Matt Brubeck
Matt Brubeck
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Chosen Solution

You can get an unofficial version of Firefox 4 that runs on Mac OS X 10.4 from http://www.floodgap.com/software/tenfourfox/

Or you can re-download Firefox 3.6 from http://www.mozilla.com/en-US/firefox/all-older.html

RCCSCA
RCCSCA Question owner
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Thanks, mbrubeck. I finally was able to reload Firefox 3.6 after a couple of tries and everything's fine. I was skeptical, but this problem solving system worked perfectly well for me this time.

1958cj
1958cj
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Perfect solution! Thank you for the link to 3.6. Exactly what info I needed. I'm running Mac OS X 10.5.8. Firefox 4.0 is not supported. Back at 3.6. Thank you!

Beth Youngdoff
Beth Youngdoff
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What is going on? I can't believe that it's virtually impossible to find a place to download the old version without going through all kinds of hoops and hoping that someone was brave enough to face the confusion of getting to the right place in order to find a replacement version. Why is system compatibility check not available before downloading? 4.0 downloaded and installed without ever stopping to check compatibility, which would have saved several hours of trying to figure out how to get the old version back (and it's no easier when you have a brain injury believe me!)

And I'll still be forced to use this sucky new version in a "short time?" Have you people totally gone off the rails?