Why does Norton Utilities fail to run if Firefox 4.0.1 is running on Win XP

Question

Platform: Windows XP
Firefox: 4.0.1
After upgrading to 4.0.1, the Norton toolbar was declared incompatible so I no longer have Norton site certification. Today (5/13/2011) I was running Firefox and tried to run Norton Utilities. It would not display the menu. But Task Manager listed it as running as well as Firefox. So I shut Firefox down and killed Norton with the Task Manager. The I clicked on NU and it ran perfectly. I have not tried to run Firefox after loading NU.

Answer 1

Firefox 4 versions and later '''do not run on a PowerPC Mac''' and require at least OS X 10.5 and '''an Intel Mac'''.
[http://www.mozilla.org/en-US/firefox/10.0.2/system-requirements/ Firefox 10.0.2 System Requirements]
The latest version for your ppc mac is 3.6.27 you can download from here:
http://www.mozilla.org/en-US/firefox/all-older.html
[http://www.mozilla.org/en-US/firefox/3.6/system-requirements/ Firefox 3.6 System Requirements]
1. Download a new copy of the Firefox program(3.6.27) from the above link
2. Trash the current Firefox application to do a clean (re-)install.
3. Install the new version that you have downloaded(3.6.27).
Your profile data is stored elsewhere in the [http://kb.mozillazine.org/Profile_folder_-_Firefox Firefox Profile Folder], so you won't lose your bookmarks or other personal data.
see also: [https://support.mozilla.org/en-US/kb/Installing%20Firefox%20on%20Mac Installing Firefox on Mac]
thank you
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