Downgrade Domain Controller Functional Level

1. Import the AD module
                      Import-Module -Name ActiveDirectory

2. Check the Forest Functional level of your Active Directory
                      Get-ADForest | Format-Table Name , ForestMode  

3. Lower the Forest Functional Level and then the Domain Functional Level
                      Set-ADForestMode –Identity “ansarsoft.com” –ForestMode Windows2008Forest 
                      Set-ADDomainMode –Identity “ansarsoft.com” –DomainMode Windows2008Domain

4. To Confirm your Forest Functional level of your Active Directory
                      Get-ADForest | Format-Table Name , ForestMode