I am getting a "Best Practices Analyzer scan has failed" error message when I try and check the best practices for the Active Directory Domain Services role on any of my 2008 R2 domain controllers. On two DCs I have successfully run this best practices scan in the past. There are no related error messages in the Application or System logs. The error appears to have started after promoting a 3rd 2008 R2 DC, although it may be unrelated. Any help would be appreciated. Thanks!