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

• http://www.mozilla.org/firefox/17.0/system-requirements/

You can find the Firefox 3.6.28 version for your OS here:

• Firefox 3.6.28: http://www.mozilla.org/en-US/firefox/all-older.html
• ftp://ftp.mozilla.org/pub/firefox/releases/latest-3.6/

For an unofficial Firefox 10.0.11 ESR compatible version (TenFourFox) that runs on PowerPC Macs with OS X 10.4.11 or OS X 10.5.8 you can look at:

• http://www.floodgap.com/software/tenfourfox/
• http://www.macupdate.com/app/mac/37761/tenfourfox

Plugins are no longer supported by TenFourFox.

• http://code.google.com/p/tenfourfox/wiki/ReleaseNotes1011
• http://code.google.com/p/tenfourfox/wiki/PluginsNoLongerSupported
• http://code.google.com/p/tenfourfox/wiki/AAATheFAQ

"You can find the Firefox 3.6.28 version for your OS here: Firefox 3.6.28: http://www.mozilla.org/en-US/firefox/all-older.html"

I tried going to this link, but it sends me to a page that says I don't meet the system requirements. Is there another link or can you tell me which folder in the FTP I should download from?

The all-older.html page used to still link to the latest Firefox 3.6.* release a month ago.

bmariew, you have not stated what OS and since this thread was started by a PPC Mac user, so assuming you are a Mac user.

Pick your language. ftp://ftp.mozilla.org/pub/firefox/releases/latest-3.6/mac/

If en-US then see ftp://ftp.mozilla.org/pub/firefox/releases/latest-3.6/mac/en-US/Firefox%203.6.28.dmg

Note that Firefox 3.6 is EOL (End Of Life) as the last security update for it was 3.6.28 back in March.

Which Mac OS X version do you have and which Firefox are you running at the moment?

See:

• https://support.mozilla.org/kb/Finding+your+Firefox+version
• https://support.mozilla.org/kb/websites-say-firefox-outdated-or-incompatible

• http://www.mozilla.org/en-US/firefox/3.6.28/system-requirements/

I have the same mac that the original post was about, mac powerbook G4 OSX 10.5.8. I don't remember what Firefox I was running as the upgrade replaced it. I have 17 now, but it won't run.

Firefox 17 and later require a Mac with an Intel processor and OS X 10.6 (Firefox 16 runs on OS X 10.5).

• http://www.mozilla.org/firefox/17.0.1/system-requirements/

For an unofficial Firefox 17.0 ESR compatible version (TenFourFox) that runs on PowerPC Macs with OS X 10.4.11 or OS X 10.5.8 you can look at:

• http://www.floodgap.com/software/tenfourfox/
• http://www.macupdate.com/app/mac/37761/tenfourfox

• http://code.google.com/p/tenfourfox/wiki/ReleaseNotes170

• http://code.google.com/p/tenfourfox/wiki/PluginsNoLongerSupported
• http://code.google.com/p/tenfourfox/wiki/QuickTimeEnabler

• http://code.google.com/p/tenfourfox/wiki/AAATheFAQ

Firefox 3.6.28 is the latest official version that runs on your computer.

• Firefox 3.6.28: http://www.mozilla.org/en-US/firefox/all-older.html
• ftp://ftp.mozilla.org/pub/firefox/releases/latest-3.6/

• http://www.mozilla.org/en-US/firefox/3.6.28/system-requirements/

@missh you could download Firefox version15 which is compatible with 10.5.8

Here is a link: ftp://ftp.mozilla.org/pub/firefox/releases/15.0.1/

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edit: replaced link as random unofficial download sites like oldapps is not needed.

You need an Intel Mac to run newer versions of Firefox. Mac OS X 10.5 on a PowerPC processor (PPC) can only run Firefox 3.6. See Firefox no longer works with Mac OS X 10.4 or PowerPC processors

There's currently a download link for Firefox 3.6 in the Install an older version of Firefox article. Here's the link for Mac OS:

• Firefox 3.6 (English US)

P.S. For Mac OS X 10.5 users with an Intel Mac, the latest version of Firefox that will work is Firefox 16. Link: Firefox 16 (US English)

Related article: Firefox no longer works with Mac OS X 10.5

Thank you cor-el, the link to the ftp you provided worked.