Enable Administror Account in Windows 7

In Windows 7, when a user with Administrator privileges is created, the default Administrator account will get deactivated and will disappear from the default login window. You can always activate it back by following the procedure given below

1. Click START Button
2. Select All Programs - > Accessories
3.  Right-click Command Prompt and then select Run as Administrator.
4. At the command promptType net user administrator /active:yes and then press Enter.
5. Restart or log off your computer and log in as Administrator.