MacBook that is compatible with macOS 10.15 or later can be restored to another compatible version. Whereas, Macs that have pre-installed 10.15 Catalina cannot be downgraded to the older versions. You may want to downgrade the 10.15 OS update to the previous one.
In this guide, we will show you how you can downgrade from 10.15.6 to 10.15.5.
Downgrade 10.15.6 Catalina to 10.15.5
Before you try to downgrade your Mac to the previous version, we would recommend you to save all the important data and files.
Start by connecting a USB drive that has 16GB or more storage space to your mac.
You will need to format the drive and rename it. From the format list, select Mac OS Extended (Journaled) and choose “GUID Partition Map”.
Now “Erase” the drive and click on “Done”.
The next step is to make your external drive bootable for installing macOS Catalina.
This could be done using Terminal on Mac. Use the following command in Terminal:
sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia –volume /Volumes/(name of your USB Drive without any space)
Hit the return key. Now enter your mac’s password and again press the return key.
Press the “Y” key to confirm your action.
NOTE: The process will take some time so be patient. The terminal will tell you that the media is now available when it’s done.
Use macOS Catalina as an Installer Boot Drive
Now that you have macOS Catalina installed in your External Drive, you can boot up and install it on any mac. Here’s how you can do it:
Turn off your mac and plug in the USB Drive in the USB port.
Now turn your mac on and hold down the “Option” key.
Then select the “External Drive” with macOS Catalina on it from the list of systems to start up your computer.
Next, follow the guided steps to install macOS Catalina onto your mac.