iPhone 15 Pro IOS 18 install getting stuck on setup.

[RWC2019]

Setting up iPhone 15 Pro from a iPhone 12. I click install and the button greys out with the spin timer and it stays there. I've tried hard reset on both phones twice. Both plugged into power. I've tried it with the sim in either phone. Made sure the iPhone 12 was all up to date with IOS and apps. I've left of for 2 hours. I have noticed before it starts downloading it say it's 999 mb but when it finally gets to install it says 3.67gb? Is there anything more I can do? I'm worried if I keep doing this it will screw the brand new phone over?

[caesarome]

Have you tried leaving it for longer than 2 hours as I have noticed that some of these big updates can take ages sometimes.

Failing that have you looked on the Apple website to see if they have any advice for issues like this ?

[RWC2019]

Already looked on the Apple site. Even looked at other various forums. I don't have all day to be without a phone, 2 hours must be ample? It downloaded, prepared and verified the update it just won't install. Managed my iPhone 12 iOS 18 install in an hour so not sure why a brand new phone would take longer than that. I did think maybe skip transfer and click manually. Could I transfer after setup? I'm not paying for more iCloud storage to back up.

[daveNOS · Accepted solution]

@RWC2019 It does seem to be a fairly common issue and the advice so far is to do the following,

First, you have to setup your new phone as a new phone, NOT by using your old phone.

Once you go through the initial setup, you have to download iOS18. 

After, iOS18 is downloaded, you have to go into settings and reset the phone.

Reset all settings (but keep eSims if you have them).

After the phone resets, you go through the initial setup again, but this time you can use your old phone to setup and transfer data.

[RWC2019]

That worked a treat, thank you.