Adprep was unable to make an LDAP connection to the Active Directory Domain Controller %1. Status/Consequence Adprep requires ...

Adprep was unable to make an LDAP connection to the Active Directory Domain Controller %1. [Status/Consequence] Adprep requires connectivity to the local Active Directory Domain Controllers that are to be prepared. [User Action]  Verify connectivity to the Active Directory Domain Controller that holds the infrastructure or schema master role, and then restart Adprep.