I was on iOS 18.1 beta 6 on my iPhone 14 Pro Max when my iPhone 16 Pro Max arrived. I took it out of the box and started to set it up as usual. I scanned the moving blue circle with my camera and began setting up the device. When I reached the software update screen, it was going to update to iOS 18.0.1. The phone restarted, and everything seemed normal. However, it brought me back to another update screen, asking me to go through the same setup steps again, which I found odd. This time, the update was for iOS 18.1 beta 7. After the update, the device restarted and appeared to be good to go, but it wasn’t. It wouldn’t go past the lock screen and kept respringing when I held down the power button to turn it off.
I tried to restore the device from my computer using Apple devices, and it began to restore. The Apple logo appeared on the black screen with a loading bar, but it got stuck at about 15%. It remained like that for over an hour while plugged in. I hard restarted the device, following Apple Support’s directions, and the device became corrupted, stuck on the restore screen. I attempted to restore it again from my computer, but it only gave error codes and once again stalled at 15% of the loading bar. The error and videos and images are linked below one error is not in pictures but it was unexpected error 3503 could not complete update and restore.
Betas are Apple Original, they are developer betas as I have a developer account.
For help with restoring your phone, please post in the Apple Support Community. The Apple Developer Forums are for questions about APIs and features intended specifically for developers.