To enable this account, type this command & hit Enter:
Net user administrator /active:yes
To disable this account, type this command & hit Enter:
Net user administrator /active:no
If you decide need a password for the administrator's account that you are going to activate or if you are unable to activate it with a blank password:
Net user administrator P@$$w0rd
Net user administrator activate:yes
Hit enter. You will get a message: The command completed successfully.
(Where P@$$w0rd has been taken as an example password)
Switch user and log on using this password.