Exchange Best Practice Analyzer shows the following message after it has been run:
The Write DACL inherit (group) right for the Exchange Enterprise Servers group should be removed from the root of the domain
To solve this issue you have to do the following. Start a Powershell mode with the Administrative Rights. Run the following command
Remove-ADPermission "dc=domain,dc=local" -user "domain\Exchange Enterprise Servers" -AccessRights WriteDACL -InheritedObjectType Groep
This command will remove writerights of the the Exchange Enterprise servers from the RootDomain.
More information: http://technet.microsoft.com/en-us/library/ee428169(EXCHG.80).aspx