Unable to install macOS Monterey (macOS 12)

Question

Created Jun ’21

Replies 4

Boosts 0

Views 7.8k

Participants 5

I want to install macOS Monterey but it doesn't allow me as it said 'Failed to Personalise the update. Please Try again.' Can you please help me fix it as I am a developer and I need help to install Monterey on my M1 MacBook Air. Here are the actions that I did which led to this error:

Downloaded and Installed the macOS Monterey Beta from the Developer Site
Opened the Installer directly by double clicking it
Chose Macintosh HD (Main Startup Drive) to install macOS Monterey Beta.
Installer stuck at 52 Minutes remaining before speeding up to an error popup.
Error Popup, the popup shows:

‘Failed to personalise the update. Please try again.’ 6. Repeated Step 2+3 Multiple times and tried again many times 7. Nothing had improved

The results I expected was the installer requesting for a restart and successfully installing the Beta after the restart. The results I saw was the ‘Failed to personalise the update. Please try again.’ As shown above in the steps, I had tried this multiple times but nothing had improved and everything was not what expected. STEPS THAT I TRIED TO FIX IT BUT WAS NOT SUCCESSFUL:

Restarted the computer
Restarted the installer
Asked developer support for help (developer.apple.com/support)

If you can solve this and get me going into installing the Operating System, that’ll be great.

Thanks everyone!

Boost

Answer 1

Claude31 OP

Jun ’21

Hope you MB is a spare computer, not your main. It is always very risky to install a beta OS on the main development computer.

0

Answer 2

schlupps OP

Jun ’21

HT211983 (klick) describes this behavior and offers a solution, but.. the solution sounds sort of tough =/

0

Answer 3

Fjfuente OP

Oct ’21

Hi, I have the same problem. the installation stops when there are 52 minutes left to go.

have you found the solution?

If so, I would be grateful if you could share it.

thanks and best regards,

1

Answer 4

seebeatty OP

Oct ’21

I was able to resolve this issue. I had the exact same experience (52 minutes remaining).

I went the revive route which requires another Mac. I follow the steps in the support document: https://support.apple.com/guide/apple-configurator-2/revive-or-restore-a-mac-with-apple-silicon-apdd5f3c75ad/mac

On the non-affected computer, I download the IPSW image from the developer site. To be used shortly.

Be certain to use the RIGHT cable (I hate that USB-C cables are different) if you follow the keystrokes and you don't get the DFU in the AC2 window, you most likely have the wrong cable. The keystroke sequence is rather forgiving. Follow the support article to get the affected computer in DFU mode.

Drag and drop the IPSW image onto the DFU image. Select REVIVE at the menu that pops up.

After allowing the process to complete, I returned to attempt running the "Install Beta" in my application folder. This time it progressed to 31 minutes and stalled. I repeated the entire process.

I think I went through the process a total of three times. The key is probably to be patient with it and allow it to complete (without touching the keyboard) Mine rebooted and got into a loop of constant chimes/reboots once - I just returned to the DFU mode and started the revive again.

On the third time, it ran the downloaded "Install Beta" program all the way through. After which, I found that I needed to check for updates and this time it found one (Beta 9) and successfully installed.

I hope this helps someone. If you are like me, it was a very frustrating situation (state of limbo). I had this problem on Beta 8 and hoped that it would work on Beta 9,... when Beta 9 didn't install, I knew I was going to need to take matters in my own hands.

0