From Windows Server 2008 R2, you can recover Active Directory deleted objects. Your forest functional level must be at least 2008 R2 in order to use this feature. Sometimes, It can be useful to permanently empty the contents of this recycling bin.
You can perform this task using Windows PowerShell. Simply use the Get-ADObject cmdlet and pipe the result to the Remove-ADObject cmdlet:
Get-ADObject -Filter 'isDeleted -eq $true -and Name -like "*USERNAME*"' -IncludeDeletedObjects | Remove-ADObject
Don’t forget the -IncludeDeletedObjects parameter. You also can add -Confirm:$false if you don’t want to confirm each deletion individually.
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