After downloading new v.5, as directed, I can't install because get message that an earlier version already exists in this location--applications forder--and I don't have permission.
Mac OS 10.7, on MacBook Pro 3.1
If you have problems with updating or with the permissions then easiest is to download the full version and trash the currently installed version to do a clean install of the new version.
Download a new copy of the Firefox program and save the DMG file to the desktop
- Firefox 5.0.x: http://www.mozilla.com/en-US/firefox/all.html
- Firefox 3.6.x: http://www.mozilla.com/en-US/firefox/all-older.html
- Trash the current Firefox application to do a clean (re-)install
- Install the new version that you have downloaded
Your profile data is stored elsewhere in the Firefox Profile Folder, so you won't lose your bookmarks and other personal data.