How to Reset Administrator Password in Windows Server 2008

Boot server from Microsoft Windows Server 2008 DVD.

From the Install Windows Menu click “Next” .

Select “Repair your Computer”.

In the System Recovery Options, Select the Operating System instance that you wish to repair and click “Next”.

Select “Command Prompt”.
 At the Command Prompt, run the following Commands:
C:\>
           C:\>cd windows
           C:\WINDOWS\system32>
           ren Utilman.exe Utilman.exe.old
           copy cmd.exe Utilman.exe

Reboot the Server allowing Windows to load normally.

At the Logon Screen, Press Windows Key + U.

At the Command Prompt, Enter following command:

net user administrator 123-zxc

This will set the Password for the Administrator user to be 123-zxc