Apple ID won't sign in on Big Sur

Had a same problem with MacBook Air 2015. Just solved it with following way:

• Create a new administrator account through 'Users & Group'
• Restart and log in through new user account created
• Use the same Apple ID for setting up the profile

Hope it will solve the issue. Thanks.

I have problems with Apple ID on Apple Macbook Air (2015) with Big Sur. Using icloud.com, I can address my Apple ID. Everything seems fine there. But when I try to login in System, I fall in a loop where I repeatedly fill in my Apple ID name and code, without anything happening. Checking my account on iCloud.com on another computer, I see that I'm regarded to be logged in. But I'm not. I cannot see my mails.

When I boot in Safe Mode: same problem.

When I add an extra administrator account, I can open a (new) Apple ID. But not in my own administrator account. Annoying.

Are you running any anti - virus programs? Using a VPN?

Try setting up another admin user account in System Preferences/Users & Groups to see if the same problem continues. Also try the Safe Mode. 

Isolating an issue by using another user account   

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Tried setting up another admin account and I was able to successfully logged in using my Apple ID. Tried using it on my primary admin account but it's still not allowing me to sign in. This is frustrating. I should have not upgraded if I knew that this problem will occur.

I also have this problem, on a 2016 macbook iirc, The toolbar at the top of the desktop screen is non-existent and I can't open the app store or safari. I can open system preferences but when I log into my apple ID it just gets stuck in the login loop. Just the macOS superiority I suppose.

I don't think that is the answer, I have had two factor authentication on since it was offered. I am only having an issue signing in on one of my machines and not even in a test user account on the same machine I am not able to sign in with.

Thank you! I have been banging my head on my desk for a couple of months now. Including talking to Apple Support. All of them advising a reinstall of OS, even though it works with another account. Clearly it was an account related issue not an OS level issue. This solved my problem. Thank you!

I just purchased a MacBook Pro 16" with the exact same issues. Tried setting up another admin, no change. Updated to Big Sur, still no change. The Mac will not allow me to log into iCloud and I cannot add/sync my phone and the Mac. I will try setting up the two step authentication next. What a disappointment with a next Mac.

I have the same problem.

I haven't figured it out yet.

It's as if my mac book doesn't have any permission to attempt to login to my apple ID.

Obviously I am putting the right username and password (I just logged in here to make this comment), but somehow the mac book loops back to that login page.

Very annoying indeed.

I had exactly the same problem. But don't worry: it's easy to solve: you have to create a new admin user and log in there. After that, everything worked out just fine. System, App Store etc. everything worked well. Hope it works also for you! Jesus bless you

I have the exact same problem on my Mac. Very annoying.

Actually, I thought I was on this post with my reply: https://discussions.apple.com/thread/252052369?answerId=254265519022#254265519022

tcantin's post solved my problem

See if anything here helps.

User Account – Combine Two

Are you running any anti - virus programs? Using a VPN?

Did you try logging in while booted into the Safe Mode?

I was just finally able to fix this by adding two factor authentication to apple id, which I had refused to do previously. It sounds like it's required now if you haven't already done so.