'Cannot Use Your Apple ID on This Device'

I have solved this problem after 10s of hours of investigation, and, socratic debugging. The solution is determined by the iOS version listed in the error message. The problem occurs because one or more of your newer devices is using a technology that isn't supported on an older device. You have to stop using the conflicting technology across all your devices.

If the error message lists:

• iOS 15.X - The conflicting technology is Account Recovery (either Recovery contact or Recovery Key). You need to remove your Account Recovery contact and/or your Account Recovery Key and turn Account Recovery off.
• iOS 16.2 - The conflicting technology is Advanced Data Protection (which also requires Account Recovery be setup). You need to turn both of these off.
• iOS 16.3 - The conflicting technology is Security Keys. You need to remove all your security keys and go back to using passcodes sent to trusted devices for 2 factor authentication. This will then allow you to add your older devices to Apple's list of trusted devices. After you have added *ALL* your older devices (including older Macs), you can then go back and add your security keys on one of your newer devices. The security keys will only be able to be used on the newer devices.

This article was helpful: https://macreports.com/how-to-fix-cant-use-your-apple-id-on-this-device/

I guess that this is tied to advanced data protection on your account. You will need to turn this feature off in order to use older apple devices

How to turn off advanced data protection:

• iPhone or iPad: In Settings, tap your name, then tap iCloud. Then scroll down and turn off Advanced Data Protection.
• Mac: In System Settings, click your name, then click iCloud. Then click Advanced Data Protection and click Turn Off.

see this link for further reference How to turn on Advanced Data Protection for iCloud - Apple Support

> I cannot understand the disparity between the successful online sign on using the iPad, but not the actual device itself via settings

This *is* the issue. Updates via the App store likely have stopped working.

The iPad accepts the Apple ID, but Apple's iCloud does not! You are getting the error because iCloud services is not properly authenticating. Use of Account Recovery, Advanced Data Protection, or Security Keys (which use the iCloud keyring) require all devices to be at a minimum level of iOS or MacOS, and your device that has the error is likely not able to be updated to the required OS. See my other post.

Refer to this document for ways to contact Apple ➞ Choose your country or region - Official Apple Support

Select your country (also look for "other" regions), then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.

or:

Contact Apple for support and service by telephone ➞ Contact Apple for support and service - Apple Support

I’m rich now

I can't tell you how much I appreciate you spending all the hours you did on this because I followed your directions and turned off account recovery, recovery key, my two usb fido keys, and whatever else I had to turn off and IT WORKED!!! THANK YOU FOR YOUR ANSWER!!!