Why I can’t install macOS on an external drive
I’m trying to put macOS 12 on an external drive. I formatted it in APFS, but when installing the system, the disk cannot be selected. Why?
We have already told how you can create a bootable USB flash drive for quick installation or recovery of macOS 12. You can install both on the main drive and on an external drive.
Unfortunately, certain issues and errors sometimes occur during this macOS installation.
How to prepare an external drive for installing macOS on it
1. Run Disk Utility and format to APFS with GUID Partition Scheme enabled .
2. After formatting, select the finished drive and select Convert to APFS from the context menu .
3. If the conversion was successful, you can install macOS on an external drive.
Don’t forget to turn off External Drive Boot Lock on a Mac with a T2 chip .
If an error occurs during the conversion, you will have to use a third-party utility.
4. Download and install the test version of Paragon Hard Disk Manager from the developer’s site .
5. Launch the application and find the connected drive in it.
6. Select the action to convert to GPT format from the context menu.
After the successful completion of the process, you will be able to install macOS on this external drive.