Reinstall macOS to Mac without existing macOS, admin account & startup disk

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Level 1

8 points

Reinstall macOS to Mac without existing macOS, admin account & startup disk

Hi,

I'm trying to reinstall macOS to a seriously messed up MacBook Pro 13" 2018 model. Apparently, problems with the computer started initially when update from Catalina to Big Sur failed. After the update the computer would not start and recovery attempts failed. The computer's disk has since been erased and all user accounts have been lost. The computer shows question mark folder when it's started.

Here's what I've tried so far:

Started Mac to startup manager (press ⌥ in startup). No disks are showing, only option is internet recovery, which fails.
Started Mac in recovery mode and ran First Aid on the disk, which says that the volume appears to be OK. In addition to internal Apple SSD, there is a macOS Base System Disk Image.
In recovery mode terminal, I've ran following commands

$ bless --info
$ bless --getBoot

which both return

Can't access "efi-boot-device" NVRAM variable.

Reset NVRAM and SMC, which had no effect.
Tried to install macOS from bootable USB memory (created following these instructions https://support.apple.com/en-us/HT201372), which fails because external boot is disallowed in Startup Security Utility. I cannot change the setting because the computer has no administrator account.
Tried to start into single user mode (⌘-S), to delete /var/db/.AppleSetupDone file in order to run Mac setup again and get new admin account. However, logging into single user mode fails, apparently because there is no startup disk (based on this: https://discussions.apple.com/thread/8448671). It just shows question mark folder even if I press the ⌘-S key combination in startup.
Tried to set startup volume in recovery mode terminal by running command

$ bless -mount /Volumes/Macintosh\ HD/ -setBoot

which returns the following:

Can't load /Volumes/Machintosh HD/usr/standalone/i386/apfs.efi

Could not load apfs.efi data from /Volumes/Machintosh HD/usr/standalone/i386/apfs.efi

Any ideas what I should do? I'm starting to be out of ideas. I'm guessing that the first thing I need is to get startup disk working and create an administrator account. However, that seems to be easier said than done

MacBook Pro with Touch Bar

Posted on Jan 14, 2021 11:51 PM

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Answer 1

Top-ranking reply

steve626

Level 6

11,231 points

Jan 15, 2021 1:45 PM in response to latape

Unless someone here has a good idea, you may need to call Apple Support or go to an authorized Apple service provider that is open -- some of the third party ones are in fact open for business. Your Mac is fairly new and should be recoverable.

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Answer 2

PRP_53

Level 10

91,195 points

Jan 15, 2021 1:54 PM in response to steve626

If going that route - be sure the Third Party Repair outfit is Apple Authorized Repair Shop. There are those who claim they fix Apple Products but. . . arrive at own conclusions. Have read many people on these forums who cut corners and ended up basically loosing the machine and having to buy a new one in the bargain.

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Answer 3

steve626

Level 6

11,231 points

Jan 15, 2021 2:00 PM in response to PRP_53

P. Phillips wrote:

If going that route - be sure the Third Party Repair outfit is Apple Authorized Repair Shop. There are those who claim they fix Apple Products but. . . arrive at own conclusions. Have read many people on these forums who cut corners and ended up basically loosing the machine and having to buy a new one in the bargain.

Yes, and you can find the Apple Authorized Shops listed on Apple's own web site, in fact. In some cases you can make a reservation/appointment through the official Apple web site. In some ways, going through one of these authorized repair centers can be preferable to an Apple Store because you can often speak in person (social distanced of course!) with the technician actually doing the work. I've had good experience with both the authorized shops and Apple Stores for service, but in the Apple Store you need to interact through another person. Sometimes the actual technicians offer insights or options that are useful to know about.

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Answer 4

PRP_53

Level 10

91,195 points

Jan 15, 2021 4:43 AM in response to latape

Give this a try. Shutdown computer and disconnect all external drives. Restart in Internet Recovery Mode (Command + Option +r ) immediately at startup. Will need Wifi Password. Once loaded, choose utilities and Security Features and might be able to get to Boot from External Drive option.

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Answer 5

latape Author

Level 1

8 points

Feb 8, 2021 11:07 PM in response to steve626

After pretty much every imaginable solution failed, I took it to authorized Apple repair. The ran diagnostics on the computer and apparently the memory modules had failed. They had to replace the motherboard to fix it. Luckily the laptop was less than 2 years old so the costs were charged from the retailer.

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Answer 6

PRP_53

Level 10

91,195 points

Jan 15, 2021 1:39 PM in response to latape

Only an opinion - it is looking like one may need to create a Bootable Installer of Catalina and use that to Erase and Clean Install Catalina. As mentioned - only opinion.

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Answer 7

latape Author

Level 1

8 points

Jan 15, 2021 10:24 AM in response to PRP_53

I just get the "No administrator was found" error.

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Reinstall macOS to Mac without existing macOS, admin account & startup disk

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