Windows 10 not displaying login name or missing last login name

Windows 10 when connected to Azure AD stops showing the last login name or any of hte login accounts.

Not sure why, had a look and found different solutions.

Seems we need to merge a few together.

Issue 

Windows 10 does not show last logged in user name.

Potentially does not show any user names.

Doesn't give any clues as to whom is logging in.

Solution

Windows Registry Editor Version 5.00

​

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System]​

"HideFastUserSwitching"=dword:00000001​

"dontdisplaylastusername"=dword:00000000

First option enables fast user account switching & second confirms that the username is displayed.

Either by itself does not work.

You need both.

Save as a reg file and run.