iPhone 15 Pro: Apple ID update "Verification Failed

It's one of those vague Apple messages which could have a lot of reasons and solutions, even beyond the suggestions I make. I propose some but in the end there's a lot of things only Apple will know and therefore my referring to Apple.

In your case there's --> System requirements for iCloud - Apple Support"

iCloud is supported on the following OS versions or later: iOS 11 on

iPhone 5s, iPad (5th generation), iPad Pro, or iPad mini 2; watchOS 4 on

an Apple Watch; macOS High Sierra 10.13 on a Mac; tvOS 11 on an Apple

TV (4th generation); or visionOS 1 on an Apple Vision Pro. Certain

features may have different requirements which are listed below. "

You can use different accounts for your general sign-in, and media and app purchases, if you have reason to.

Well, Limnos, you've been around and maybe that is why your reply felt a bit "abrupt"! This problem is all over the web, and this community, and there seems to be no easy answer. Most of us, have done these things and navigated to the links you suggest - and they don't work.

Even though I'm 100% sure I'm entering the correct credentials they are rejected. Even stripping the iPhone down to factory settings and then rebuilding it, i.e. not restoring it, and trying to create a completely new AID, I get the same response. The AID server cannot verify.

Could it be that the verification has somehow "moved on" and that my naked iPhone running 9.3.6 (those days when we could have an iTunes and and iCloud account with different credentials) has outlived the AID concept? I don't seem to have the problem with my MAC A4 or iPhone 13 both OS26.x - but to be honest, I haven't got the courage to disconnect them and see if they will survive.

Another view, I tried to create a new Apple Account, with a new email address and new password. The system does not respond - it hangs and then just closes the app. This is telling me that there is something in this iPhone that is not compatible and my thinking is that, while it has been connected for 8-10 YEARS, when it ran out of battery was required to restart and sign in again - and the characteristics of this older iPhone and OS is somehow excluding it from connecting to Apple ID?

It is possible since its iOS far pre-dates the the iOS11 in the article to which I posted a link. I haven't tried booting my old iOS9 devices in a few years (I have them in my next recycling trip pile) to check if they even can connect now.

Try restarting your device.

If you are using a VPN remove it completely. Don't just turn it off.

If you can't connect or sign in to iCloud, read this support article --> If you can't connect or sign in to iCloud - Apple Support In particular check server status.

Ask Apple:

You can reach Apple Support using this link --> Contact - Official Apple Support

or by telephone at one of the numbers in this support article --> Contact Apple Support - Apple Support