Attention Mac Users: Old Lightroom & Photoshop Versions Won't Reinstall under New Catalina OS

(This post has been edited to reflect that older versions of Lightroom & Photoshop may run under macOS 10.15, but you will not be able to uninstall, reinstall, or reactivate these programs. -- 08-15-2019, KSE)

Apple has announced plans for a new operating system (OS) version called Catalina (10.15) that they will release in late September. Catalina will be a completely 64-bit OS, meaning than any 32-bit applications will NOT run under this system.

If you are currently using a Mac and running Lightroom 6/2015 or older or Photoshop 2018 (version 19) or older, you will not be able to uninstall, reinstall or reactivate either of these applications under Catalina. That's because these versions use a 32-bit installer program that is incompatible with macOS 10.15.

Therefore, if you want to continue using your older versions of Lightroom and/or Photoshop, you should not install Catalina when this operating system upgrade becomes available.

My colleague Laura Shoe has written a helpful blog post on this topic, which also includes a link to an Adobe post about the effects of this Mac OS change on Lightroom and Photoshop. I encourage all Mac users to read it:

Mac Users of Lightroom 6 and Earlier Versions: Don’t Install Mac OS Catalina! by Laura Shoe

Knowing this change is coming, you have three choices:
  1. Keep your Mac OS on the Mojave (10.14) operating system and continue to use your older versions of Lightroom and Photoshop. You may want to update your Lightroom to 6.14 so you are at the newest release of that version.
  2. Upgrade to the Photography Plan, the subscription model of the current version of Lightroom. Adobe is working with Apple to ensure Lightroom (both Classic and cloud-based) works with the Catalina OS.
  3. Move to a different photo editing program that runs under the new Mac OS. Note that regardless of the application, it may take some time before the manufacturer releases a version that's compatible with the new operating system.
Knowing this change is coming from Apple gives you some time to decide how you want to respond to it. Also, please share this post with any of your Mac user friends so they are aware of the coming changes.