To avoid surprises and other possible issues during the process, it is a very good idea to validate the current version of the schema before and after the ADPREP process has been completed. To find the current Active Directory Schema Version, you can use one of the following methods:
ADSIEdit.msc
Navigate to: CN=Schema,CN=Configuration,DC=domain,DC=local and review the current objectVersion attribute by clicking on the Properties of CN=Schema,CN=Configuration,DC=domain,DC=local.
LDP.exe
Connect and Bind to one of your DCs using the ldp.exe tool. Click on view and then tree. The BASE DN isCN=Schema,CN=Configuration,DC=domain,DC=local.
DSQuery
Open a command prompt and use this command: The following information provides a mapping between the objectVersion attribute value, to the Active Directory Schema version:
13 -> Windows 2000 Server30 -> Windows Server 200331 -> Windows Server 2003 R244 -> Windows Server 200847 -> Windows Server 2008 R251 -> Windows Server 2012
