procedure TForm25.DoPage(H_Pdf:TIEPdfViewer);
Begin
   Self.Caption:='--Load--';
   H_Pdf.LoadFromFile('C:\Temp\IenBug\UniGUI.pdf');
   For Var I:=0 to H_Pdf.PageCount-1 do
       H_Pdf.PageIndex:=I;
   Self.Caption:='--OK--';
End;

procedure TForm25.BitBtn1Click(Sender: TObject);
begin
    Var ien:=TImageEnView.Create(Nil);
    Try
        ien.PdfViewer.Enabled := True;

        DoPage(ien.PdfViewer);//is OK#65281;
    Finally
       ien.Free;
    End;
end;

procedure TForm25.BitBtn2Click(Sender: TObject);
begin
    Var PdfViewer:=TIEPdfViewer.Create();
    Try
        DoPage(PdfViewer);//Bug  H_Pdf.PageIndex:=I;
    Finally
       PdfViewer.Free;
    End;
end;