Revised MacOS Catalina‌‌ Supplemental Update Released

Oct 21, 2019 - 13 Comments

MacOS Catalina

Apple has released a new revised version of the MacOS Catalina Supplemental Update that was initially released last week.

It’s unclear why a revised version of the supplemental update was made available, or if any new features or changes are included. Release notes accompanying the download remain the same, however.

The newly updated MacOS Catalina Supplemental Update brings macOS 10.15 to build 19A603 (whereas the prior weeks supplemental build was 19A602).

Installing Revised MacOS Catalina 10.15 Supplemental Update

Always backup Mac with Time Machine or your preferred backup method before installing any system software update.

  1. Go to the  Apple menu and choose “System Preferences”
  2. Select “Software Update”
  3. Choose ‘Update’ on the MacOS Catalina 10.15 Supplemental Update

If other updates are available that you want to avoid, remember that you can selectively install specific software updates in MacOS.

On the other hand, if you’re running a prior macOS release and you’re currently wishing to avoid Catalina for whatever reason, you can learn how to hide MacOS Catalina from Software Update on Mac here.

Release Notes for Revised MacOS Catalina Supplemental Update

Release notes accompanying the revised supplemental update are the same as the prior supplemental update:

“The ‌‌macOS Catalina‌‌ Supplemental Update includes installation and reliability improvements, and is recommended for all users.

This update:

– Improves installation reliability of ‌‌macOS Catalina‌‌ on Macs with low disk space

– Fixes an issue that prevented Setup Assistant from completing during some installations

– Resolves an issue that prevents accepting iCloud Terms and Conditions when multiple ‌‌iCloud‌‌ accounts are logged in

– Improves the reliability of saving Game Center data when playing Apple Arcade games offline”

It’s unclear why Apple didn’t rename the new build of the update as “macOS Catalina‌‌ Supplemental Update 2” or something more clearly distinct, though it’s possible the revision is merely addressing an issue specific to the prior supplemental update.

MacOS Catalina installs and works fine for most Mac users, but some users have reported various problems with the new macOS 10.15 operating system. If you’re running MacOS Catalina, you should update to the latest software updates as they become available.


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Posted by: Paul Horowitz in Mac OS, News


» Comments RSS Feed

  1. JohnIL says:

    I wish Apple would be more forthright about what these updates address. For now I reverted back to Mojave until things become more stable. I tried to do a clean install of Catalina but got errors doing a clean network install so I just went back to Mojave. I’ll give Catalina six months to bake and improve before trying it again. I didn’t see anything in it I really wanted or needed anyway.

  2. Bertie says:

    I have a mid 2012 MacBook Pro 13″ and getting same response. Auto updates is not turned on. Also having problems trying to set up mail. Any ideas? Have seen another mail app on the App Store, but that is not letting me download. Oh, what fun. Bet it wouldn’t have happened when Jobsy was about.

  3. Wayne says:

    Well the previous os install (last week) hosed my macbook pro Mid-2012 13″ so maybe this update is for folks like me. Presently my mac is stuck in a reboot mode. I have been busy and i dont need my mac right now. I will deal with this when I get free time

    • chembeat says:

      Mine (13″ mid 2012) to, exact same problem. Got it to boot up by letting it stay on for a while. But it still got random crashes and freezes when in Catalina. Don’t know if I want to install the new update? Afraid for more problems. Maybe 10.15.1 is the hope to wait for?

    • Ladi says:

      Mine is an early 2015 model and equally crashed. stuck in this reboot mode

  4. Jeff says:

    Just tried to install from system preferences:

    Revised MacOS Catalina‌‌ Supplemental Update Released

    I get the “Your Mac is up to date…” message and version 10.15 (19A602) rather than 603 still shows as being currently installed.

  5. PaulL says:

    Just tried Software Update…it says I’m up to date without downloading this supplemental release. Oh well.

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