How to Enable / Activate Hidden Administrator Account in Windows?

Many people ask me why there is no built-in Administrator account available in Windows Vista, Windows 7 and later OS versions? Why can't we use the default Administrator account? The answer is "Yes! The default Administrator account is still created in Windows Vista and later OS but its disabled by default for security purposes."
Many times you might want to enable it for troubleshooting purposes or to get rid of the annoying UAC prompts while tweaking your system. So here I'll describe a few methods to enable and activate the hidden and built-in Administrator account in Windows Vista, Windows 7 and later OS versions:

Method A:

1. Right-click on My Computer icon on Desktop and select "Manage", it'll open "Computer Management" window. ( You can also open it by giving "compmgmt.msc" command in RUN dialog box or Start Menu Search box).

2. Go to "Local Users and Groups -> Users" section. In right-side pane double-click on "Administrator" account. It'll open its Properties window. Uncheck "Account is disabled" option and Apply it.

Method B:

1. Type "secpol.msc" in RUN dialog box or Start Menu search box, it'll open "Local Security Policy" window.
2. Go to "Local Policies -> Security Options".
3. Double-click on first option "Accounts: Administrator account status" and select "Enabled" and apply it.

Method C:

1. Click on "Start button -> All Programs -> Accessories". Right-click on "Command Prompt" and select "Run As Administrator". If you are prompted to enter password, enter the password and continue. You can also open Command Prompt in Administrator mode by typing "cmd" in Start Menu Search box and press "Ctrl+Shift+Enter".
2. Now provide following command:

net user administrator /active:yes

3. That's it. The Administrator account will be enabled. If you want to disable it again, simply replace "yes" with "no" in above command.

NOTE: Never activate the hidden Administrator account until required. Its better to use other general accounts for better security. Also the Administrator account has no password, so if you enable it then don't forget to set a strong password for it.