System.InvalidOperationException: Active Directory Client is not installed on this computer.
   at System.DirectoryServices.Interop.UnsafeNativeMethods.ADsOpenObject(String path, String userName, String password, Int32 flags, Guid& iid, Object& ppObject)
   at System.DirectoryServices.DirectoryEntry.Bind(Boolean throwIfFail)
   at System.DirectoryServices.DirectoryEntry.Bind()
   at System.DirectoryServices.DirectoryEntry.get_IsContainer()
   at System.DirectoryServices.DirectoryEntries.ChildEnumerator..ctor(DirectoryEntry container)
   at System.DirectoryServices.DirectoryEntries.GetEnumerator()