Raising the Domain Functional Level
Raising the domain functional level determine which Operating Systems can be used for domain controllers and which features of Windows Server 2003 are enabled. The lower the level, the fewer the features are supported.
Windows Server 2003/2008
Windows Server 2003/2008
1. Click Start | Administrative Tools | Active Directory Users and Computers
2. Click Action, select All Tasks and select Raise Domain Functional Level
3. Click the drop down to select the available functional level. Windows 2000 Native is the default. Click Raise
4. Caution: Once you click Yes there is no turning back. Click OK. What Raising Domain Functional Level does is setting what Server can become domain controller. By setting the domain functional level to Windows Server 2003, only Server running Windows Server 2003 or above can be demote to domain controller.
5. Click OK