Install Active Directory in Windows Server 2008 and 2003 are similar

-        Click start à Run à Type Dcpromo à Click Nex

- Click Next 

-  Choose Domain Controller for a new domain & Click next

 -        Choose Domain a new forest and Click next

- Choose No, Just install and configure DNS on this computer, and click next

- put DNS name for new domain. Ex: Angkor.edu.kh, and click next.

-        Chang Netbios Domain Name (no need to change)

Ex: ANGKOR

-        Here you can change Database and log folders(no need to change) click next.

-        this is sharing system volume(no need to change), click next.

-        Select Second option for not allow other user to view information on server, and click next.

-        Here is put password for login to our server and click next.

-        this summary of information about install active directory and click next. Please waiting a few minute, and click finish, and restart you server. Later on you will see you server had been promoted.

 Note: when you install Active directory you need folder of windows server 2003 is I386.