With Mac OS X 10.4 and below you can not upgrade to Firefox 4.0, nor with a Mac 10.5 without Intel.

So it is 3.6.17 that you want to download. You are too far behind to trying to use updates, the reason you are behind is that the update is probably stuck.

To download the latest 3.6 version (3.6.17) start at http://www.mozilla.com/firefox/all-older.html and download the latest version. At the completion of the download don't let the setup start Firefox for you, when the setup ends, start Firefox in your normal manner this way you will be less likely to create a new profile.

The extra startup pages are temporary -- read them. The next time Firefox comes up you should be back to starting with your normal home page.

Note: Firefox must be down once the install starts. Close Firefox with File>Exit. Then make sure Firefox is not running -- On Windows: check the "Processes" tab in the Windows Task Manager. On Mac: Firefox > Quit then Command+option+Esc, if Firefox running use Force quit

Permission errors on Mac: If you were getting permission errors on a Mac, download the latest Firefox version, then uninstall and reinstall Firefox. Do not remove your profile directories and files as they contain your settings, bookmarks, history, extensions, passwords, and cookies.

Thanks so much, I now have the newer version. I tried to update it through the update pop up but it didn't work for some reason.

Thanks again for the help, I appreciate it.

For an unofficial Firefox 4 compatible version (tenfourfox) that runs on a PowerPC Mac with OS X 10.4.11 or OS X 10.5.8 you can look at:

• http://www.floodgap.com/software/tenfourfox/

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

• http://www.mozilla.com/en-US/firefox/all-older.html

Thanks for your help. Is the unofficial Firefox 4 compatible version safe? Is it a part of Firefox? Do I need Intel?

The version from http://www.floodgap.com/software/tenfourfox/ only works on PowerPC Macs (Intel users with 10.4 are out of luck) and has been developed for users with a PPC Mac that have OS X 10.4.11 or 10.5.8. The TenFourFox version is based on the Firefox 4 or later code.

See the "Tuned for your operating system and processor" section on http://www.floodgap.com/software/tenfourfox/