Undo Built-in Administrator Account tied to a Microsoft Account

Somehow or another I received a computer to work on in which the build is Administrator account has been tied to a MSA. It is Windows 10 Home so I can't get to more advanced options in lusrmgr. I've tried searching and haven't found anything related to this topic; I have no Idea how the MSA was tied to the Admin account and there is no sign out/switch to local option. I tried to reset the Admin account as described here, but it did not remove the MSA.

Any ideas?
Thanks in advance.

Converseallstar95 said:

Somehow or another I received a computer to work on in which the build is Administrator account has been tied to a MSA....

This is theoretically not possible. Unfortunately there is one unique set of circumstances in which it can happen. As far as I know Microsoft provide no way of undoing it (as they never intended it to be possible in the first place). @Kari knows the details...

Kari said:

I have now replicated your situation and can confirm the loophole in Windows 10 you have accidentally found. I installed Windows 7, activated the built-in administrator account and removed all other user accounts. I then upgraded to Windows 10 which after the upgrade naturally had only this one user account, the built-in administrator account.

This allowed me to connect the built-in administrator account in Windows 10 to a Microsoft account and use Windows Store to download apps. Notice that because the default restrictions, this is normally not possible; when the built-in admin account is used as it should, not as a sign-in account to Windows but solely for administrative tasks it is not possible to use most of the Windows Apps with it (Store, Edge and so on), and it cannot be converted to a Microsoft Account.

The loophole you found, activating the built-in admin in previous version and then upgrading to Windows 10 using it seems to override all default security restrictions on the said built-in admin account, making it possible to connect it to a Microsoft account. However, as this is meant never to happen, once you have converted the built-in admin account to a Microsoft account, it is no longer possible to convert it back to a local account. It is absolutely impossible....

How to remove Microsoft Account from the Hidden Administrator (post #10)

Brink said:

Could it be that the built-in Administrator may just be signed in to the Store app with the Microsoft account?

cereberus said:

OPs post does not make sense....

@Brink & @cereberus. Unfortunately for the OP, Kari has shown that not only is it possible, but it's irreversible too

Brink said:

Hello @Converseallstar95, :)

Could it be that the built-in Administrator may just be signed in to the Store app with the Microsoft account?

If so, then you could reset the "Microsoft Store" app back to default to see if that may remove the association.

Reset App in Windows 10 Apps Features Tutorials

If not, then check to see if it may be listed using step 3 in Option Two below, and can be removed.

Add or Delete Account in Windows 10 Mail app Browsers Email Tutorials

Hi Brink, thanks for the response; I have checked the Microsoft Store, yet the MSA is NOT signed into the store.

cereberus said:

OPs post does not make sense. The built in and normally hidden Administrator account cannot login with an MSA account and does not run uwp apps.

I think OP is confusing the Administrator account with the default Admin account initially setup which can be a local or MS account - the installer tries very hard to get you to use MSA as we all know.

Thank you for trying to help; I understand that while my account may look inexperienced (including the typo "build is" rather than "built in"), I am far from it. I did mean the built-in Administrator account is logged in with an MSA, as others have commented on below. Understandably, you didn't know, as it was new information to me as well!

Bree said:

This is theoretically not possible. Unfortunately there is one unique set of circumstances in which it can happen. As far as I know Microsoft provide no way of undoing it (as they never intended it to be possible in the first place). @Kari knows the details...

How to remove Microsoft Account from the Hidden Administrator (post #10)

My apologies, I wouldn't have posted a new thread if I had found that thread. You may merge them if you'd like.

Kari said:

No, that will not fix it.

I've been testing this now quite extensively because I found something that makes me worried; as of version 1709 it is now possible to use UWP apps also when signed in as built-in admin. This was not possible earlier. If tried, an error message like below was shown:



Now, with full access to UWP apps it means that, although it still is not possible to switch built-in admin account to a Microsoft account from Settings > Accounts, it is now possible to sign to UWP apps with MS account when signed to Windows as built-in admin and from there switch the system account to a Microsoft account when choosing wrong:



In my opinion this is a serious error, something that should not be possible and allowed.

When the built-in admin account has been connected to a Microsoft account, the only way to revert it, switch back to a local account is a clean install. The link to switch to a local account is simply missing:



For repair install, there's nothing to repair; the account is OK and working.

Kari

Here are some screens from the laptop. It sounds like there is no way besides a clean install.

Screenshot 1: No MSA signed into the Microsoft Store
Screenshot 2: MSA signed into Administrator account with no option to switch to local
Screenshot 3: No MSA linked to Email and Accounts
Screenshot 4: netplwiz options - no option to reset password (since it is an MSA)
Screenshot 5: netplwiz properties - shows it is the built in account

Other notes:
I can load all the UWP apps without error
If I press forgot password from the login window I am taken to the Cortana reset MSA password experience

Kari said:

Once the built-in admin account has been switched to a Microsoft account, there's no way to switch it back to a local account. Absolutely nothing you can do. Only way to undo it is a clean install.

Kari

Ok; thanks for the help!