“Other user” option missing from Azure AD-joined PC login screen

While working on an issue yesterday, I disconnected a client’s PC from Azure AD, which I assumed, would let me log in with a local account. However, I found that the login screen displayed only the now-disconnected Azure AD user account and no “Other user” option.

I found that if you set any entry here to 1, it will appear at the login screen: HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\CurrentVersion\Winlogon\SpecialAccounts\UserList

Fortunately, our RMM lets us modify the registry, so I flipped that bit on a known local admin account, and after rebooting, I could log in!

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