Active Directory does not exist or cannot be contacted [CannotAccessAD]
Exchange Setup can't continue because it can't contact a valid Active Directory site. Setup requires that the target server is able to locate the configuration naming context in Active Directory.
To resolve this issue, verify that the account that you're using an Active Directory account to run Setup and then try running Setup again. If this doesn't resolve the issue, follow the guidance about using the support tools in the following topics to further diagnose the problem.
For more information about Active Directory troubleshooting and configuration for Exchange, see the following topics:
Having problems? Ask for help in the Exchange forums. Visit the forums at: Exchange Server.