Apple has just released OS X 10.11 El Capitan GM, but users and developers running beta builds will not be able to upgrade directly from the App Store. In order to upgrade from a El Capitan beta build, for example, seed 15A278b to the El Capitan GM release 15A282b, you’ll need to jump through a few minor hoops first.
- Launch the App Store, but instead of going to the “Updates” page (where you’ll see none), go to the “Purchases” page.
- If you’ve previously installed an El Capitan build, you’ll find “OS X El Capitan GM Candidate” in the list of purchases, alongside a button to download:
- Selecting “Download” will bring up a warning dialog stating that this will download the entire installation image instead of updating, and advising you to “Update” instead – unfortunately, at the time of this writing this is not an option and you must click “Continue” to download anyway:
- The OS X App Store will begin to download the entire image – yes, all 6.06 GiB – as apparently there is no delta update at this time:
- Once the download has finished, the installation should begin. If not, you can manually launch the install from the same page. Make sure to back up your Mac before starting the upgrade.
Update: Based off of an email Apple has sent beta testers, it does not seem that there will be a delta update made available for current beta testers:
If you are currently testing OS X El Capitan, please back up your Mac and do the following to install the GM Candidate. Go to your Purchased tab in the Mac App Store and click the Download button next to OS X El Capitan GM Candidate. When your download finishes, the installer will automatically launch.
Follow the onscreen instructions to complete installation.