Apple = Mac. Two questions: (1) Is the problem that Firefox starts going through the motions of upgrading but fails, or that it never even tries? (2) Do you use Firefox Sync? There have been changes in the service and before you update Firefox, someone should advise you on that. ---- If Firefox isn't trying to update, you can use the Help menu's About Firefox dialog to kick off the process. Or if you can't upgrade normally, you can install Firefox again. Don't remove your personal settings, you want to keep those in place. You can download Firefox 37.0.2 from the following page (scroll down to your language): https://www.mozilla.org/firefox/all/ Then see: [[How to download and install Firefox on Mac]].