How to downgrade a domain functional level?

Question

Active Directory

Good afternoon! You need to downgrade the domain functional level from Windows Server 2008R2 to Windows Server 2008. Didn't include the AD Recycle Bin. According to the recommendations, I wanted to try to complete the task according to the following article https://blogs.technet.microsoft.com/aman/2012/12/2...
When executing the Get-ADForest command in PowerShell, an error occurs, I attach the screen.
From PowerShell to YOU. Help)

Answer 1

This video explains it well:
https://www.youtube.com/watch?v=raUpczIJHOk