MacOS Big Sur 11.4 Apple ID Login Loop

Hello, aragorn_iii.

I understand you can login to the iMac but from there you have no systemwide access to iCloud services; your Apple ID and password do not appear to work.

• Reboot the iMac. If rebooting your Mac doesn’t fix things, see if the problem still happens in Safe mode (hold the shift key down at startup). It can take much longer (10 min) to safe boot so be patient.

How to use safe mode on your Mac - Apple Support 

You might also try this:

• Reset the NVRAM

How to Reset NVRAM / PRAM on your Mac - Apple Support

If neither of these remedies solves the problem, you can do this:

• REINSTALL macOS (NON-DESTRUCTIVELY) - This will reinstall a fresh copy of the OS on top of the current copy without altering your current files and such.

To reinstall macOS as a troubleshooting measure - without deleting user files, documents, pics and vids, etc. – restart your Mac using the key combination Command (⌘)-R until you see the Apple logo. When the macOS Utilities window appears, select "Reinstall macOS" then follow the onscreen instructions.

How to reinstall macOS - Apple Support:

https://support.apple.com/en-us/HT204904

NOTE– You should NOT have to erase, delete, format, partition or otherwise alter your startup disk for this. If that appears to become an option, quit the process and restart your Mac. Then come back here for additional advice.

EDIT - Please ensure you have a current and up-to-date backup before you do this... just in case.

The Log In for the Computer is not the same a log in to Apple ID. These are two completely and separate things and perform tow comply actions. Changing your Apple ID password will not change the Computer Password.

To change the Computer Password >>

Reset Computer Password 

Intel Computer

1 - Restart computer and immediately hold Command + r keys

2 - Top Tool Bar >> Utilities >> Terminal

3 - Type resetpassword as one word and no spaces

4 - Press Return key

5 - Follow the prompts and remember the New Password

M1 Computer 

1 - Choose Apple menu > > Shut Down.

2 - Press and hold the power button on your Mac until you see “Loading startup options.”

3 - Click Options, then click Continue. 

4 - Top Tool Bar >> Utilities >> Terminal

5 - Type resetpassword as one word and no spaces

6 - Press Return key

7 - Follow the prompts and remember the New Password

Very good. You have solve your own issue.

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