Windows 11: Administrator Microsoft account disappeared from the sign-in screen after changing ConsentPromptBehaviorUser

Windows version

Windows 11 Home

Version: 10.0.26200.8655

Problem

I changed the following registry value:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ConsentPromptBehaviorUser

from 3 to 1 after following advice from Microsoft Copilot. After testing, I restored it back to 3. No other registry values were changed.

Immediately after this, I noticed several unexpected issues.

Symptoms

My original administrator Microsoft account (profile folder: C:\Users\kone_) disappeared from the Windows sign-in screen.

The account still exists.

net user shows the account.

The account is active.

The user profile still exists.

The account also appears in Control Panel user accounts.

The administrator Microsoft account disappeared only from the sign-in screen. It is still present in net user, Control Panel, and its user profile directory.

Windows Hello fingerprint authentication still works normally.

The PIN cannot be removed because the Remove PIN button is greyed out.

Selecting Change PIN opens an empty dialog containing only a Cancel button.

UAC now prefers the Windows Hello fingerprint prompt. I would like it to default to a password prompt instead.

Things I have already checked

Registry values:

EnableLUA = 1

ConsentPromptBehaviorAdmin = 5

ConsentPromptBehaviorUser = 3 (restored)

PromptOnSecureDesktop = 1

Other checks:

• net user reports the missing administrator account as active.
• certutil -csp "Microsoft Passport Key Storage Provider" -key successfully lists a Windows Hello key.
• dsregcmd /status reports NgcSet : NO, although Windows Hello fingerprint authentication still works.
• The PC is not joined to Azure AD, a domain, or an organization account.

Question

Has anyone seen this combination of symptoms before?

These issues started immediately after changing ConsentPromptBehaviorUser from 3 to 1 and then restoring it to 3. According to Microsoft's documentation, this registry value should not affect the Windows sign-in screen or Windows Hello PIN management, which makes this behavior unexpected.

Could this have triggered a Windows bug, or is there another Windows component that may have become corrupted?

Is there a supported way to restore the missing administrator Microsoft account to the sign-in screen and repair the Windows Hello PIN management UI without recreating the affected Microsoft account?