Active Directory Installation Wizard is a wizard on a machine running Microsoft Windows Server that installs Active Directory service on a member server, turning it into a domain controller.
You can use Active Directory Installation Wizard to:
- Create a new domain controller with a new domain tree
- Create a new domain controller with a new child domain that is located under a parent domain in an existing domain tree
- Create a replica domain controller for an existing domain

How it works
You must be an administrator to run Active Directory Installation Wizard. Start the wizard by running the dcpromo utility from the command prompt, or choose the Run command from the Start menu, enter dcpromo in the Run dialog box, and then click OK.
This opens the wizard’s welcome screen, where you are required to make a number of decisions concerning the following:
- Whether to create a new domain or add a replica domain controller to an existing domain
- If you choose to create a new domain, whether to create a new domain tree or add a child domain to an existing tree
- If you choose to create a new domain tree, whether to create a new domain forest or add the new tree to an existing forest
Names you specify for new or existing domains, domain trees, or domain forests are based on the Domain Name System (DNS) naming system. Other steps in the wizard allow you to specify the path to the Active Directory database, the location of the SYSVOL share, and so on.
These are the results of running Active Directory Installation Wizard:
- The machine on which the wizard is run becomes a domain controller. If it is the first domain controller in your domain, the wizard also creates a new site for that controller. If it is the first domain in your enterprise, it is also the root domain for any domain tree that will be created. You can use the wizard to create the first domain forest in your enterprise too.
- The first domain controller is also your global catalog server.
- Active Directory files are located in %SystemRoot%\Ntds with the associated log files.
- The shared system volume SYSVOL, which stores scripts used for implementing group policies for your domain, is located in %SystemRoot%\Sysvol.
- A number of default organizational units (OUs) are created, namely the Users, Builtin, Computers, and Domain Controllers.
Install DNS first
You must make sure that DNS is already installed and configured prior to running Active Directory Installation Wizard in order to create the first domain controller for your network. A DNS name will be needed for your new domain controller, and a DNS server must be available on the network during the installation process.
NTFS volume required
Active Directory files also require an NTFS volume, which must be configured as a basic volume. Dynamic volumes cannot be used for Active Directory files. Running the wizard creates a log file in the %SystemRoot%\Debug folder that shows the results of the installation procedure.
If you are creating a new child domain, there must be an available domain controller on the existing parent domain. If you are creating a replica domain controller, there must be an available domain controller in the target domain.
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