iMac 12,1 21.5" Mid 2011 Issues Updating OS

Question

iMac 12,1 21.5" Mid 2011 Issues Updating OS

Trying to make this computer useful for a friend...It has a hard drive that cannot be erased but is still recognized as a device. Attempting to install High Sierra on an external drive and operate the computer from that.

Cannot install any Boot Rom updaters such as: Mac EFI Security Update 2015-001

Boot Roms are version 52 and should be version 55

It cannot boot from a USB drive or install any system on a USB drive

It does boot from Firewire 800 drive with El Capitan and Sierra. I have installed both systems using this computer but he rom version never updates.

It will NOT install High Sierra saying that a Firmware Partition is missing.

Any input on how to get the boot roms to update and get it to boot from USB along with that High Sierra install issue would be appreciated. At this point attempting to install High Sierra on the Firewire 800 drive unless I can get USB boot to work.

iMac 21.5", macOS 10.12

Posted on Jul 10, 2019 5:20 PM

Reply

Answer 1

Best reply

QuickPost

Level 10

103,305 points

Jul 19, 2019 7:06 PM in response to barryfromalbany

Hello,

Have you tried running Apple Hardware Test?

Apple Hardware Test

Reply

Answer 2

HWTech

Level 9

55,598 points

Jul 19, 2019 7:51 PM in response to barryfromalbany

barryfromalbany wrote:

It will NOT install High Sierra saying that a Firmware Partition is missing.

You need an internal drive installed and partitioned as GUID and formatted as MacOS Extended (Journaled). The macOS installer requires this probably so it can place the firmware updater on the internal drive.

Since you say the internal drive cannot be erased, I'm assuming it is physically failing. You can run DriveDX to check the health of the drive to confirm. If DriveDX reports the internal drive as healthy, then post the DriveDX report here using the "Additional Text" icon which looks like a piece of paper since the report can contain useful information on the health of the drive.

When trying to erase the internal drive, did you click on the physical drive in the left pane of Disk Utility or did you just try to erase the "Macintosh HD" volume? If the physical drive is not shown in the left pane of Disk Utility, then click the "View" menu and select "Show all devices". Again erase the physical drive as GUID MacOS Extended (Journaled).

Reply

iMac 12,1 21.5" Mid 2011 Issues Updating OS

Similar questions