Migrating Active Directory Domain Controller from Server 2003 to Sever 2008

1. Raise Domain Functional Level (Server 2003)

• Click Start > Administrative Tools > Active Directory User and Computers 
• Right-Click the Domain Name node. Click on Rise Domain Functional Level 

Note: If you have Windows 2000 Active Directory Domain Controllers then choose Windows 2000     Native. If you don't have any Windows 2000 AD-DC, and all of you Domain Controllers are Windows Server 2003 then choose Windows Server 2003.

• Click OK, in  a warning message
• Click OK, in a confirmation message
• Close Active Directory User and Computers

2. Prepare Forest Level and Domain Level (Server 2003)

• Insert Windows Server 2008 DVD inside the Server 2003 DVD Drive
• Run as Administrator Command Prompt
• If the DVD is Windows Server 2008 32 bit. Type D:\sources\adprep\adprep /forestprep (Where D: is the drive of your Windows Server 2008 DVD)
• If the DVD is Windows Server 2008 64 bit. Type D:\support\adprep\adprep /forestprep. Press Enter
• Read a warning message, if you don't have any Windows 2000 Active Directory, type C and then press Enter

Note: After Forest preparation is completed successfully, run the Domain prep rotation command.

• If the DVD is Windows Server 2008 32 bit Type D:\sources\adprep\adprep /domainprep (Where D: is the drive of your Windows Server 2008 DVD)  
• If the DVD is Windows Server 2008 64 bit. Type D:\support\ support \adprep /domainprep. Press Enter
• Although adprep/domainprep will update the domain-wide information. Run the last command D:\souces\adprep\adprep /domainprep/gpprep  or  D:\support\adprep\adprep /domainprep/gpprep

3. Install Active Directory Domain Services - Windows Server 2008

• Click Start, in Start Search type "dcpromo" then press Enter
• On the new Windows, click Continue button. "The setup will detect if the binaries are installed and if they are not it will install them"
• After that, following the Active Directory Domain Services Installation Wizard

4. Setting a Windows Server 2008 Domain Controller as a Global Catalog

• Click Start > Administrative Tools > Active Directory Sites and Services
• From the left panel, expand Sites > Default-First-Site-Name > Server > Domain Controllers
• Expand the Windows Server 2008 that you want to set as Global Catalog, right Click in NTDS Settings, then Click in Properties
• Click in General Tab, there is a check box beside Global Catalog. Select this check box and click on Apply then OK

5. Transferring FSMO Roles in Windows Server 2008

Using Active Directory Schema snap-in to transfer the Schema Master Role. You have to register schmmgmt.dll in order to be able to use the Active Directory Schema snap-in.

• Click Start > Run
• Type regsvr32 schmmgmt.dll
• A message information will confirm that schmmgmt.dll was successfully registered. Click OK
• Click Start > Run 
• Type mmc, and click OK
• Click File > Add/Remove snap-in...
• From the left side, under Available Snap-ins. Click to select Active Directory Schema, then click Add, and click OK
• Right click Active Directory Schema > Change Active Directory Domain Controller...
• Select This Domain Controller or AD LDS instance. Click on the Domain Controller that you want to be the Schema Master role and then click OK
• You will receive a message box, click OK
• In the console tree, right click Active Directory Schema (Domain Controller.Domain Name), and then click Operations Master...
• Click Change
• Click Yes to confirm the role transfer, and a new confirmation message will be displayed, click OK
• In Change Schema Master windows, click Close 

Using Active Directory Domains and Trusts snap-in to transfer the Domain Naming Master Role.

• Click Start > Administrative Tools > Active Directory Domains and Trusts
• Right click Active Directory Domains and Trust, then click Change Active Directory Domain Controller...
• Select This Domain Controller or AD LDS instance. Click on the Domain Controller that you want to be the Schema Master role and then click OK
• Right click Active Directory Domains and Trust, then click Operation Master..
• Click Change
• Click Yes to confirm the role transfer, and a new confirmation message will be displayed, click OK
• On Operation Master windows, click Close 

Using Active Directory Users and Computers snap-in to transfer the RID Master, PDC Emulator, and Infrastructure Master Roles.

• Click Start > Administrative Tools > Active Directory Users and Computers
• Right click Active Directory Users and Computers, click All Task > Operation Master...
• Click Change button under each of these three tabs (RID, PDC, Infrastructure)
• Click Yes to confirm the role transfer, and a new confirmation message will be displayed, click OK
• When you click Change button on Infrastructure role, you will receive a message. Click Yes