Administrator rights lost

hi,
i first create a new user and made him admin
i remove my self from the admin group
disable the built in administrator
change his password for a stronger one
and i hide the new local user admin from the log screen in the registy
after what i have lost the admin rigth
i try reboot safe mode but no admin account shows up neither the build in one neigther the one i create later.
i also try reboot whit my rapaire usb in command line (xsource) net user administrator /active:yes
reboot in safemode again and no admin shows up there too.

that's the tutorial that bring me in trouble

How to hide specific user accounts from the sign-in screen on Windows 10 | Windows Central

thanks for help
windows version 1909 (os build 183633.535)

yvesd said:

... i have lost the admin rigth...

Welcome to Ten Forums yvesd.

See if this tutorial helps you.

Fix UAC prompt has grayed out or missing Yes button in Windows 10

it didn't help, thanks anyway

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i resolved it this way:
YouTube
when i reboot Administrator was there so i can reverse the change have made before in the registry. Now i wonder if i can hide my local admin account without go thru this again and lose administration power completely. how is that possible that something that is just hidden act like he is disable ?

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i have found this, it work but i still dont understand the logic behind all this

ALWAYS display the last / default user Windows 7 welcome screen - Super User

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies
create the key CredUI and than inside the key a valueDWORD EnumerateAdministrators