Sorry, but as you discovered, Firefox 4+ no longer support the PowerPC CPUs.

I recommend backing up your Firefox settings in case something goes wrong with the reinstall. See Backing up your information. (You can copy your entire Firefox profile folder somewhere outside of the Mozilla folder.)

Next, download and save Firefox 3.6 from here: http://www.mozilla.com/firefox/all-older

Does that work (i.e., pick up your profile automatically)?

There's also an unofficial build using Firefox 5 code adapted to the PPC platform. You can read about that here: http://www.floodgap.com/software/tenfourfox/

Thanks for the help but I still have problems. 1.I replaced Firefox3 with firefox 4 when that dialog box opened during the install so all I'm left with is Firefox4 in my application folder and it wont open. 2.The link to the back up page wont work can you type out the url. 3.Would there be somplace on my computer besides Firefox 4 where the bookmarks are stored

Thanks George

Here's the relevant part of the article: how to find your Firefox profile on disk so you can make a copy in a safe place. Do this in Finder, not in Firefox.

https://support.mozilla.com/en-US/kb/Backing%20up%20your%20information#w_locate-your-profile-folder

(If you don't see a picture of Finder, look in the right column for the operating system selector and choose MacOS)

After that, reload 3.6 from http://www.mozilla.com/firefox/all-older and see whether it works.

Thank You ,thank you thank you, when I downloaded 3.6.18 1nd replaced 4 all my book marks showed up. Perfect help

George