Error:
“Naming Information cannot be located for the following reasons”
“The Server is not operational”

You receive the above error when launching Active Directory on a Windows 2008 server. You may also find numerous DNS errors within your event log and your users experience authentication issues.

Resolution:

Temporarily disable AV (A high chance you are using McAfee). If this resolves your issue, there is a hotfix available. Click here

Also install hot fix at http://support.microsoft.com/default.aspx?scid=kb;EN-US;961775