Checking proper promotion

After promoting a Windows Server installation to a read-only domain controller, it's recommended practice to check for proper promotion. Follow these steps to check:

Check the logs: The following two files contain all of the actions performed when promoting the Windows Server installation to a domain controller. A good way to check against improper promotion is to search for lines containing error and warning, as shown in the following example:
- C:\Windows\Debug\dcpromo.log
- C:\Windows\Debug\dcpromoui.log
Check the event viewer: In the event viewer, eventvwr.exe, new dedicated logs are created for Active Directory Domain Services. Search these logs for any Active Directory-related errors.
Run Windows updates: Even though one of the recommended steps is to update the Windows Server installation you intend to promote to a read-only domain controller, it's also a recommended step to install Windows updates after the Windows Server installation has been promoted, as updates apply to the newly installed server roles and features, too. These role-specific updates are only applied after the role is installed.