Big Sur won't even reinstall on my new m1 MBP

I had the same issue but I fixed it! Putting the sick Mac into DFU mode and using a second Mac to restore it is the only thing I've found that works to fix the issue. See this Apple support article on the procedure.

A couple of important notes:

• The USB-C cable MUST support both USB power and data. Many cheap cables don't. Many thunderbolt cables don't! If in doubt, use the original Apple cable.
• The USB-C cable MUST be plugged into the LEFT (rearmost) USB port of the sick machine. This is the opposite of Intel Macs. The other end must be plugged into another Mac running the latest version of Apple Configurator 2 (currently 2.13.2). The sick Mac WILL NOT go into DFU mode unless these conditions are met.
• To go into DFU mode, starting with the sick Mac turned completely off, press and hold POWER + RIGHT_SHIFT + LEFT_CONTROL + LEFT_OPTION all at the same time. You must press them all at once and keep them held down. After 10 seconds (count to 10) you release all but the POWER BUTTON. When the Mac running Configurator shows DFU in the "All Devices" section (a few seconds later), let go of the POWER button.
  • Yes, this procedure is ridiculous; Apple really doesn't want people getting into it accidentally.
• I know the "Restore" action works, but be aware this will erase your computer. You can try the "Revive" action first if you want (this should keep your data) but I seriously doubt that this will work.

hui209 wrote:

I received my new m1 chip MBP today and I tried to reinstall the Mac OS because I sync with the wrong iCloud ID, so reinstallation should be the easiest way for me to erase all the files. 

I erased the disk and everything but the installer just keeps saying ”An error occurred preparing the update. Failed to personalize the software update. Please try again”. 

The system won't install, and now my Mac has no OS at all !

I don’t know what to do, I mean it’s a brand new MBP. 

https://support.apple.com/guide/mac-help/macos-recovery-a-mac-apple-silicon-mchl82829c17/11.0/mac/11.0

Call Customer Support (800) MY–APPLE (800–692–7753)

This cable:

USB-C Charge Cable (2 m) - Apple

which ships with the the Power adapter for battery-capable Macs. It is NOT a general-purpose data transfer cable, it is essentially a Charge -ONLY cable.

It grudgingly accepts USB-2 signals, but only because they are required for USB Power Delivery negotiation. Listed pairings are ONLY for use with Power adapters, nothing more.

When used for data transfer, it may work, but it will be too slow to be useful in many cases. it does NOT state it is compatible at USB-3 speeds, which is what you need for disk transfer speeds.

Apple have now posted an official article regarding the problems re-installing Big Sur on the new M1 model Macs.

If you get a personalization error when reinstalling macOS on your Mac with Apple M1 chip - Apple Support

I was aware of the above article and issue before I erased my new M1 Mac and specifically upgraded to macOS 11.0.1 before rebooting in to recovery mode and erasing the Mac. Despite the fact I went out of my way to upgrade as advised to 11.0.1 the same problem has occurred and it is currently bricked. I am now trying the various steps supposedly only needed for macOS 11.0 to fix the Mac.

(I needed to reinstall as I had a problem first time around with DEP enrolment.)

Apple have really dropped the ball here.

Apple also need to start thinking hard about the size of macOS installers and the fact that no recovery media is included. Yes in many cases the Recovery HD partition may be sufficient but certainly not all as this case illustrates. Furthermore even though I have a reasonably fast Internet link with no usage cap this is certainly not true for all Apple's customers even in the developed world so having to re-download over the Internet over 12GB of macOS installer potentially multiple times is unacceptable. It is taking me nearly two hours per attempt.

Solutions Apple could consider would be a version of macOS installer burnt in to read-only memory aka a ROM, or including a USB flash drive. The later was briefly used as a means of distributing MacOS in the ancient past.

Clearly macOS is only going to continue to gain bloat making this matter worse. It is already the case that macOS is a huge fatty compared to Linux or even Windows 10. (Admittedly this time around a lot of the excess weight macOS is carrying is due to much of the code being universal binaries.)

I tried all three approaches in Apple's support document https://support.apple.com/en-us/HT211983 after using Apple Configurator (use the Reinstall macOS Big Sur utility, use a bootable installer, and use Terminal to reinstall). The Reinstall macOS Big Sur utility gave the same error ("An error occurred preparing the update. Failed to personalise the software update. Please try again."). The bootable installer gave the same error. The Terminal approach gave the error, "This copy of the Install macOS Big Sur application is damaged and can't be used to install macOS". I'm appalled that Apple's own support document created to fix this specific bug failed so catastrophically, necessitating taking the computer back to Apple for repairs.

Those options will not fix hui209's issue, he/she is already trying to do the reinstallation option of Big Sur in the Recovery OS and it fails with an error. From what I gathered talking with support this seems to be an issue if you do not upgrade to Big Sur 11.01 prior to a reinstall.

Support and I were able to restore/reset my M1 Macbook Pro by using the DFU recovery option in Apple Configurator 2; this option does require you to have another Mac though and one that has a USB-C port I believe. I do not think there is an option to fix this other than the DFU recovery mode at this point as we also tried a reinstallation from a USB stick and Time Machine restore - both failed. If you do not have another Mac to try the DFU recovery option you will probably need to take the M1 Mac into an Apple Store and have them complete the recovery option for you.

• To try the DFU restore option you will need to take the USB-C cable that came with the M1 Macbook and plug the cable into the rear USB-C port on the M1 Macbook (the one closest to the screen) and then plug the other end of the USB-C cable into your other Mac.
• Next you will have to have downloaded Apple Configurator 2 from the App Store on your working Mac.
• Open Apple Configurator 2 after it has downloaded.
• On the M1 Macbook shut it down. Make sure there are no external drives plugged into the M1 Mac.
• From there you have to put it into the DFU recovery mode which can be done by pressing and holding: Left Control + Left Option + Right Shift + Power Button all for 10 seconds, then release the buttons and press and hold the Power Button until the M1 Mac shows up in Apple Configurator 2 on your working Mac - it should show DFU. If you do not see the Mac show up in Apple Configurator 2 as DFU then it did not connect properly and you will have to try again. If you do not get the M1 Mac to connect properly in Apple Configurator 2 in DFU mode then your best bet is to take it to the Apple Store.
• Once the M1 Mac shows up in Apple Configurator 2 in DFU mode, click on the M1 Mac to select it.
• Go to Actions in the menu bar and then select Restore. This should download a reinstallation image try to restore the M1 Mac. I will note that this did fail the first time for me and I tried again (I believe this is because I had a USB drive plugged into the M1 Mac) but it did work the second time. You will be prompted a couple of times during the Restore, unfortunately I don't remember the prompts but there were pretty self explanatory and I think it was pretty clear what option to click.

Hopefully that can help some people, but if you don't feel comfortable doing this or need more explanation/don't have a second Mac your best bet is to go to an Apple Store or call support and see if they can offer help/solutions.

Total side note but I did all of the reinstallation and account setup on battery on the M1 Mac and it only used like 10% battery in 5 hours which was pretty nuts. The Macbook Pro 16" I was using to restore the M1 Macbook with chewed through 40% battery during this process. Crazy...

I had the same issue and DFU mode is the only thing I've found that works to fix the issue. A couple of things to check:

• The USB-C cable MUST support both USB power and data. Many cheap cables don't. Many thunderbolt cables don't! If in doubt, use the original Apple cable.
• The USB-C cable MUST be plugged into the LEFT (rearmost) USB port of the sick machine. This is the opposite of Intel Macs. The other end must be plugged into another Mac running the latest version of Apple Configurator 2 (currently 2.13.2). The sick Mac WILL NOT go into DFU mode unless these conditions are met.
• To go into DFU mode, with the sick Mac turned completely off, press and hold POWER + RIGHT_SHIFT + LEFT_CONTROL + LEFT_OPTION all at the same time. You must press them all at once and keep them held down. After 10 seconds (count to 10) you release all but the POWER BUTTON. When the Mac running Configurator shows DFU in the "All Devices" section (a few seconds later), let go of the POWER button.
  • Yes, this procedure is ridiculous; Apple really doesn't want people getting into it accidentally.
• I know the "Restore" action works, but be aware this will erase your computer. You can try the "Revive" action first if you want (this should keep your data) but I seriously doubt that this will work.

I have the same issue, I'm guessing the logs will need to be passed to some developers for investigation; I have a lot of errors show up in the logs when I try a reinstallation from the recovery os - something like over 12,000 errors. My assumption is that this is only a problem on the new M1 macs right now but it may be affecting others as well.

I have the same issue. Can't install Big Sur from USB nor internet due to the ”An error occurred preparing the update. Failed to personalize the software update. Please try again”.  Restore from TimeMachine won't work either since the only backup I have is with Catalina.

Also, can't get into DFU mode to restore the macOS via Apple Configurator 2.

Don't know what else to try.

sgilder_'s post got me thinking. Had tried to enter DFU mode over 20 times but was using the cable included with my 2017 MBP. After swapping that older cable with the m1 MBP included cable, was able to enter DFU mode the first try! Recovery option is now complete. Hope this helps someone else.

Apple chat support seems sure it was a wireless network issue, I tried a wired connection and the result was the same. I have a time set up for next Tuesday to do the DFU mode + Apple Configurator 2 fix at the Apple store.

The cable included with your 2017 MacBook Pro is likely a CHARGE-ONLY cable. These have no high speed data pathways at all -- at best, they have low-speed USB-2 suitable for a keyboard or mouse.

If I were King, it would paint the ends of these Charge-only cables Bright orange or something to distinguish them from "real" cables.

This is not true! AFAIK, Apple has never shipped a USB-C cable with a Mac that was charge-only. Since many Thunderbolt cables out there do NOT support USB data, this is actually your best bet for a compatible cable. Stop spreading FUD! Don't post speculation; unless you know something is true don't post it.

This is literally the first sentence of the description in the link you provided:

"This 2-meter charge cable — with USB-C connectors on both ends — is ideal for charging, syncing, and transferring data between USB-C devices."

USB-C does do what used to be called USB 3.0 (now something like 3.1 low-speed IIRC). It's half as fast as 3.1 high-speed, but still extremely fast for this purpose, as others have testified to. It only takes about 10 minutes to transfer everything.

Trust me when I say that this cable does work--i used it myself to fix this issue.

Now you're crossing into deliberately spreading inaccurate information--to people desperate to fix their problem--to avoid losing face. Don't do that; it's not nice.