Can not restore OS on Mac Book Pro 2019 (16 inch)

floabr wrote:

Last error during recovery is "Operation failed OSISUarchiveMobileSoftwareUpdateOperation

Operation queue failed with error : Error Domain =com.apple.OSIINstallerSetup.error code=1004 "An error occured loading the update"

Hi

I upgraded my Mac OS on my MacBook Pro 2019 16 inch to Sequoia(15.1) but the Safari Browser was crashing intermittently. I then installed Firefox and it did the same, so I presumed Sequoia has issues with my hardware or my OS installation was corrupt, so I tried to downgrade back to Catalina (10.15).

To restore the OS back to Catalina (10.15) I am using the recovery method (as I cant boot to the OS anymore), I am pressing various keys (command/option/shift etc) and the R 1. key before the apple logo on boot up, this then tries to install Catalina (10.15) or Sequoia (15.1) depending on the keys I press - all of these fail to install.

So when I try to use recovery with Command R it tries to recover Catolina and fails, when I try with Cmd Opt R (it tries the latest compatible OS) which fails to install Sequoia (15.1). I have now hit several roadblocks and I can't boot to an OS anymore, I cant go back to using Sequoia or go back further to using Catalina (10.15), so can anyone who understands how to get out of this situation please help me !

I also downloaded Senoma on to a USB key and created a bootable USB installation. When I try to use this to recover the device it tells me I need to use the Security Utility to remove permissions that are blocking the USB as an installer, when I then run the Security Utility it refuses to let me remove the permissions as there is No Admin account setup on the device - I presume I can only add an Admin account once I am logged in to an OS - so catch 22.

Now my Macbook Pro no longer boots to any OS, any suggestions involving using an OS already installed will not work for me. When the machine starts up all I get is

I have tried the following

Install Catalina using internet recovery - gets about 98% done and fails

Install Sequoia (15.1) using installer 20.1.01 - again using internet recovery (see pic

https://discussions.apple.com/content/attachment/25217cfd-84eb-4b8b-9853-9f9f70f817ff

ture) also gets about 98% done and then fails. I accept the TOS and the log says No IAL Update Found then it tries to download it and the recovery GUI stays visible,progress bar 98% complete, then "An Error occurred loading the update1. ". The wifi is defintely working (checked Wifi router activity, also I can see IP address allocation) - tried both a 5G and a 2.4G wifi connection. The installer log file says

I also downloaded a Semona DMG installer and made a bootable installer USB key (using Windows) - this is recognised by the installer successfully on startup, but when I try to use it as a recovery image it says I need to turn off security permissions - so I restart and run the security utility - then it says to login to change the settings, but then tells me there is no Administrator account.

How on Earth do I get this thing back up and installed, I have been a software engineer for 30 years, built several of my own PCs etc and I can not for the life of me figure out why this is so complicated and unreliable.

<Install Log File.log>

see if this gets you any further.

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Then you should follow the good guidance of @leroydouglas and set an appointment for service at an Apple Store or service provider.