I’ve tried everything I’ve read about trying to reinstall High Sierra on a Mac Mini model A1347. I erased my disk and am trying to install macOS High Sierra. When I select the disk I want to install to, it is grayed out and says it’s locked. I have absolutely no option to unlock the disk.
[Re-Titled by Moderator]
Earlier Mac models
Is this an internal drive that you are trying to install the OS on?
I suspect you may not have erased the disk, but rather just a volume that is on that drive.
When you boot to recovery mode, launch Disk Utility and then you MUST click View > Show All Devices. Only then can you select the drive device and properly erase and reformat it.
How to reinstall macOS - Apple Support
Click on the small box in the upper left corner and select Show All Devices.
Then:
1) select the Hitachi HTS545050.... in the sidebar and post a screenshot of the Disk Utility panel.
2) select the indented Volumes below that and post a second screenshot of the Disk Utility panel.
Ignore OS X Base System. That is not usable nor is it accessible for this purpose. Only the OS gets to use that.
You need to install the OS to the Hitachi drive listed above.
For macOS High Sierra you should erase and format it with Mac OS Extended (Journaled) and give it a GUID Partition Map scheme. You should also name it "Macintosh HD" as that is the default.
Exactly what error or message are you seeing when this all fails?
You need to boot into Internet Recovery Mode using Command + Option + R. If you don't, then the system will be booting to that internal drive that has a partial image of the macOS installer on it. You cannot erase the same drive you are booted from, which is why you cannot select it.
When you do erase it, then make sure to erase the Hitachi item.
If you want to erase the whole internal device you must boot from another device, from a bootable USB macOS installer or from Internet Recovery.
If you choose Internet Recovery, remember to use this workaround because Apple is too lazy to fix it:
Another option might be to boot from the local Recovery volume as you apparently can do. I guess you could then create a new MacOS Extended partition to it and install there.
Thank you, but it’s wiped as well.
It won’t let me erase it, only options clickable are partition and first aid for the Hitachi disk
Disk option is grayed out when installing High Sierra on my Mac mini
