That aside, see the steps below for how to install a second version of macOS on a computer. It's easy to set up, much more flexible than the old method, and that means you no longer have to choose how much space to permanently assign to a partition, although the option is also available if you want. Using a feature called Space Sharing, you can create multiple volumes in a container and automatically share storage space between them if needed.Īll you have to do is create a new volume, download the second version of macOS to this location, then select the new volume when starting your computer. If you have macOS High Sierra (10.3) or later, your computer will by default use the APFS format required for this method to work. But that changed when Apple switched from a file system called Mac OS Extended to use the Apple File System (APFS).

Previously, installing two versions of macOS on a Mac required creating a dedicated partition on your drive and allocating some storage space to it. APFS makes it easy to install multiple versions of macOS Other uses include testing the software with different versions of macOS or using it to safely install beta versions of macOS. If you use professional software that often has compatibility issues with recent macOS updates, this is a great solution, as it allows you to continue running it on your version of macOS. If you have macOS 10.13 or later, you can simply create an APFS volume and use that location to install the second version of macOS you want. Not many people know that it's possible to have two versions of macOS installed on your Mac at the same time - you should have no trouble partitioning your drive.

Instal the new for mac Optimizer 15.4