You cannot update to Firefox 4 or 5 because they support only Mac OS X 10.5 and above on Intel hardware (details can be found [http://www.mozilla.com/en-US/firefox/system-requirements.html here)]. <BR><BR> Instead, you can install Firefox 3.6 by following these steps: # Open the ''Applications'' folder. # Drag the ''Firefox'' application to the ''Trash''. # Download and install Firefox 3.6 from [http://www.mozilla.com/en-US/firefox/all-older.html here]. Instructions for this step can be found here: [[Installing Firefox on Mac]].

If you have Mac OS X 10.3 or less then you can't update to more recent Firefox versions. * http://www.mozilla.com/firefox/3.6/system-requirements/ * http://www.mozilla.com/firefox/2.0/system-requirements/