Windows 7 - run as administrator doesnt ask for password

Local computer with Windows 7 Professional was connected to domain XXX.local. I switched it to local group YYY.

After reboot I have one account ZZZ with no admin rights. When I try to open UAC or other settings that require Administrator account it fails. Windows prompt window opens but I assume that it cannot find administrator account and it doesnt show password prompt and button Yes is disabled.

When I check users that are in this computer there is Administrator (disabled) and ZZZ. I cannot turn on Administrator account or change ZZZ group because I cannot run it because it requires Administrator rights :)

What can I do to grant user ZZZ administrator rights?

Answer

There are a few ways you can go here.

If you can rejoin the pc back to the domain, you can then use an account with domain credentials to give ZZZ administrative rights.

An obvious answer is to wipe everything and start over.

It is possible to hack your windows system and grant your user administrative rights. In order to do this, you will need to boot using a windows installation medium. This can be windows 7 or windows 10.

From the setup, open a command window (SHIFT-F10) and execute the following command:

copy c:\windows\system32\sethc.exe c:\windows\system32\sethc.exe~
copy c:\windows\system32\cmd.exe c:\windows\system32\sethc.exe

Reboot your computer and make sure you end up at the logon screen. If it automatically logs you in, log out first.

Now press shift 5 times to open a command prompt.

From here, you can use the following command to gain administrative privileges:

net localgroup administrators ZZZ /add

From here you can also reset your password or create a new user.

Don't forget to boot back into the windows setup and execute the following commands from a command window:

copy c:\windows\system32\sethc.exe~ c:\windows\system32\sethc.exe

This will restore the sticky keys functionality and patch the security vulnerability we created.

EDIT: Just to clarify, this only works for windows 7. Windows 8 and 10 have different methods that works nearly the same but this specific instructionset on option 3 will not work.