In can't install Firefox 3.6.3 on my iMac 10.5.8. I always get the message saying I don't have the requested authorization to install some elements, despite I'm amdinistrator of the iMac

See http://kb.mozillazine.org/Installing_Firefox#Mac_OS_X ..... Download a new copy of the Firefox program: http://www.mozilla.com/firefox/all.html Trash the current Firefox application to do a clean reinstall. Install the new version that you have downloaded. 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 and other personal data. See also [[Upgrading to Firefox 3.6]]