Failing reinstall of El Capitan on formatted HD - no Disk Utility (2012 iMac, white screen of death)

[CrossyTK]

Hi
My 2012 iMac (quad-core i5; 12 GB RAM, 1 TB HD) got stuck, white screen of death, as it seems. After tons of repair attempts (with all kinds of startup-key holdings), I backed-up the HD contents via my Mid 2015 PowerBook and formatted the iMac’s HD. I prepared a USB stick with the El Capitan installer, and with the USB stick in the iMac, holding the option key, I could choose the USB stick as startup disk. The Apple symbol shows up and the status bar fills to about 60% when the screen quickly goes black and then becomes completely white - and stays like that forever… I would have expected that El Capitan would install on the iMac or the Disk Utility tool would show up.
What’s wrong? (Btw: Recovery / internet recovery did not work either.) - Desperately seeking help, thanks for any useful advice!

 

[Nguyen Duc Hieu]

Hi
My 2012 iMac (quad-core i5; 12 GB RAM, 1 TB HD) got stuck, white screen of death, as it seems. After tons of repair attempts (with all kinds of startup-key holdings), I backed-up the HD contents via my Mid 2015 PowerBook and formatted the iMac’s HD. I prepared a USB stick with the El Capitan installer, and with the USB stick in the iMac, holding the option key, I could choose the USB stick as startup disk. The Apple symbol shows up and the status bar fills to about 60% when the screen quickly goes black and then becomes completely white - and stays like that forever… I would have expected that El Capitan would install on the iMac or the Disk Utility tool would show up.
What’s wrong? (Btw: Recovery / internet recovery did not work either.) - Desperately seeking help, thanks for any useful advice!

The hardcore way:
Open your iMac, replace the HDD with SSD, and redo the installation.

The easy way:
Prepare an external SSD (USB 3.0 enclosure with SSD inside).
Install Mac OS (High Sierra) to it.
Hook it to your 2012 iMac.
Do a NVRAM reset and try to boot from the external SSD.
If you could get to the Mac OS desktop, you can use Disk Utility from there.

 

[Fishrrman]

Do you have a spare external drive around?

I'd try installing El Cap to the EXTERNAL drive.
Get a copy of the OS on it, and get a basic account so you can log in and get to the finder.

Then, connect it to the iMac and boot using the "option key trick":
- Press power button
- IMMEDIATELY hold down the option key and KEEP HOLDING IT DOWN
- The startup manager should appear
- Select the external drive with the pointer and hit return.
Do you get "a good boot" this way?

If so, I recommend Nguyen's "easy way" -- leave the internal drive alone (for now, at least) and boot from an EXTERNAL drive.

The 2012 ought to have USB3, you could get an external USB3 SSD and boot and run that way. The iMac will then become quite "snappy"...

 

[CrossyTK]

The hardcore way:
Open your iMac, replace the HDD with SSD, and redo the installation.

The easy way:
Prepare an external SSD (USB 3.0 enclosure with SSD inside).
Install Mac OS (High Sierra) to it.
Hook it to your 2012 iMac.
Do a NVRAM reset and try to boot from the external SSD.
If you could get to the Mac OS desktop, you can use Disk Utility from there.

Hi, Nguyen Duc Hieu
Thank for your advice. I tried (practically) the "easy way" - but it does not work: Installation of El Capitan on either a (formatted) USB stick or on the formatted iMac HD (via Target Disk mode and Thunderbolt cable) is obviously excluded: The installer says "OS X can't be installed on this disk. macOS isn't installed" (in both cases).
Since opening the iMac is "a bit" tricky", I'l refrain from trying "the hardcore way". Also because I doubt wether that would work - given the apparent fact that El Capitan can be installed ONLY where (a suitable?!) MacOS is aready installed...
More --> please see my next response (to Fishrrman's post)

 

[CrossyTK]

Do you have a spare external drive around?

I'd try installing El Cap to the EXTERNAL drive.
Get a copy of the OS on it, and get a basic account so you can log in and get to the finder.

Then, connect it to the iMac and boot using the "option key trick":
- Press power button
- IMMEDIATELY hold down the option key and KEEP HOLDING IT DOWN
- The startup manager should appear
- Select the external drive with the pointer and hit return.
Do you get "a good boot" this way?

If so, I recommend Nguyen's "easy way" -- leave the internal drive alone (for now, at least) and boot from an EXTERNAL drive.

The 2012 ought to have USB3, you could get an external USB3 SSD and boot and run that way. The iMac will then become quite "snappy"...

Hi, Fishrrman
Installation of El Capitan on either a (formatted) USB stick or on the formatted iMac HD (via Target Disk mode and Thunderbolt cable) is obviously excluded: The installer says "OS X can't be installed on this disk. macOS isn't installed" (in both cases).
I decided to reinstall the disk image on the iMac HD. And now? Again via Target Disk mode and Thunderbolt cable, the El Capitan installer (downloaded by and onto my MacBook Pro) made possible to choose the iMac HD and accomplished the OS installation "successfully". - However, shutting down the iMac and restarting it did not let the iMac start up as it should, but the original error (white screen after abot 60% of the status bar) persists. Only, after some minutes, the white screen vanishes, and the iMac restarts by itself...
Thus: not very much gained...

 

[wordsworth]

I don't know if this will prove of any help but…

A while back I tried to update my white MacBook (early 2009) to El Capitan (from Snow Leopard). It would get so far but then would fail. It got to the point where I tried all sorts, including internet recovery. I gave up trying eventually (ran out of options) but wondered whether it was the lack of battery that was causing the problem (battery had swollen and so I'd ditched it, running it from the mains instead). I read somewhere that this could cause problems.

Last week I bought a replacement battery and tried to get El Capitan installed. Still wouldn't have it. I then remembered reading that there was a different issue some people had encountered, trying to install El Capitan on an older computer, because the installation's signing certificate was now out of date. So I tried following the instructions here (link below) and these worked for me. Basically (and I summarise), I typed into Terminal (and that part was very simple) a date (2017) that as a consequence made the certificate appear valid.

Mac stuck in "El Capitan" installer loop: "no packages were eligible for install"

My problem is that my Mac starts up to the "El Capitan" installer. After restarting several times, OS X is still on screen telling me that "no packages were eligible for install&quot...

apple.stackexchange.com

It may be that this has been part of your installation issue at some point in your own efforts? Have a look at what it says, anyway, in case it helps. Good luck.

 

[CrossyTK]

There are two points I am wondering about...

1. I looked at the lines which show up in verbose mode (CMD-V at startup). And there is something in the iMac's file system which makes me wonder, whether a former OS installation / update went wrong, such that (in a way) two systems are installed in parallel which again creates a problem...
In the verbose output, I have these lines:

> LibBootCache: Unable to open: /var/db/BootCache.playlist: 2 No such file or directory
> Warning: kextd unavailable; proceeding w/o lock for <unknown>
> Warning: couldn't block sleep during cache update
> Warning: proceeding w/o DiskArb
(later
> tzinit: New update not compatible or older version: 2020a.1.0 vs 2020a.1.0: No such file or directory
> Sun Jan 31 (more stuff here) Early Boot complete. Continuing system boot.
(later
> Notice - new kext com.apple.driver.KextExcludedList, v13.2.1 matches prelinked kext but can't determine if executables are the same (noUUIDs).
(later
> unsupported CPU
> unsupported CPU
> unsupported PCH
> HID: Legacy shim 2
> BCM5701UserClient::clientClose
> BCM5701UserClient::terminate
(later
> promiscuous mode enable succeeded

In the file system of the iMac, as visible in the Finder, I have the folders
Applications / Library / System / Users
Within "Library", there are about 60 subfolders.
But within "System", there is another folder named "Library" which contains about 97 subfolders - most of them seem to correspond to the subfolders in the upper-level "Library" folder... Is that the way it's supposed to be?? Is it rather a source of the problem? Help by simply deleting a number of files / folders from the HD...?

2. I had the diagnosis (hardware test) run (option-D at startup), and once it (again) showed a memory error: 4MEM/62/40000000: 0x88e61518 . (I suppose this is clearly a RAM error...) Only sometimes this (or a similar) error is diagnosed (in the extended test only, anyway). I am wondering whether one can tell which of the four RAM modules is the (occasionally) faulty one?
If one cannot tell, I shall go ahead and carry out some dozens of tests, I think, with the one or the other pair of RAM modules removed... (would there be something to be watched out for while doing this, such as at the first restart after a change of RAM?)

I don't know whether the two (potential) problems are independent from one another or whether perhaps the memory problem (2.) caused the OS system problem (1.)...?!
To me it seems best to firstly investigate and solve the memory problem (2.) (which apparently is present)? Or am I heading a wrong way?

Further comments & advice most welcome!

 

[CrossyTK]

I don't know if this will prove of any help but…

A while back I tried to update my white MacBook (early 2009) to El Capitan (from Snow Leopard). It would get so far but then would fail. It got to the point where I tried all sorts, including internet recovery. I gave up trying eventually (ran out of options) but wondered whether it was the lack of battery that was causing the problem (battery had swollen and so I'd ditched it, running it from the mains instead). I read somewhere that this could cause problems.

Last week I bought a replacement battery and tried to get El Capitan installed. Still wouldn't have it. I then remembered reading that there was a different issue some people had encountered, trying to install El Capitan on an older computer, because the installation's signing certificate was now out of date. So I tried following the instructions here (link below) and these worked for me. Basically (and I summarise), I typed into Terminal (and that part was very simple) a date (2017) that as a consequence made the certificate appear valid.

Mac stuck in "El Capitan" installer loop: "no packages were eligible for install"

My problem is that my Mac starts up to the "El Capitan" installer. After restarting several times, OS X is still on screen telling me that "no packages were eligible for install&quot...

apple.stackexchange.com

It may be that this has been part of your installation issue at some point in your own efforts? Have a look at what it says, anyway, in case it helps. Good luck.

Hi, Wordsworth
Thanks for your post. Currently I am not aware of how I could be able to change the time information of the iMac, as it doesn't startup... But thanks for the hint - it may be helpful later on, I suppose.

 

[Nguyen Duc Hieu]

Hi, Nguyen Duc Hieu
Thank for your advice. I tried (practically) the "easy way" - but it does not work: Installation of El Capitan on either a (formatted) USB stick or on the formatted iMac HD (via Target Disk mode and Thunderbolt cable) is obviously excluded: The installer says "OS X can't be installed on this disk. macOS isn't installed" (in both cases).
Since opening the iMac is "a bit" tricky", I'l refrain from trying "the hardcore way". Also because I doubt wether that would work - given the apparent fact that El Capitan can be installed ONLY where (a suitable?!) MacOS is aready installed...
More --> please see my next response (to Fishrrman's post)

Since installing El Capitan has failed, would you consider installing Catalina, just to get to Disk Utility?
Create the USB installer on another Mac.
Boot on your 2012 iMac
Install Catalina to the external SSD.
After installing, wipe out the internal HDD to reinstall El Capitan or High Sierra to it. I recommend High Sierra.

Create Catalina Installer from here: macOS Catalina Patcher (dosdude1.com)