API para copiar archivos

[Arnol125]

Hola de nuevo

estoy tratando de copiar unas imágenes de una carpeta compartida en red a una carpeta en disco local y uso este código pero me sale el mensaje "Acceso Denegado"
los componentes son:

Button1 - Iniciar
Button2 - Cancelar
ProgressBar1 - componente
funcion ProgressRoutine

Código Delphi [-]

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, FileCtrl, ExtCtrls, Buttons, ComCtrls;

type
  TImageForm = class(TForm)
    Button1: TButton;
    Button2: TButton;
    ProgressBar1: TProgressBar;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);

  private
    { Private declarations }
  public

 { Public declarations }
  end;

var
  ImageForm: TImageForm;
  Cancel: boolean;

implementation
 

{$R *.dfm}


function ProgressRoutine(TotalFileSize, TotalBytesTransferred, StreamSize, StreamBytesTransferred: LARGE_INTEGER; dwStreamNumber, 
dwCallbackReason: DWORD; hSourceFile, hDestinationFile: THandle; lpData: Pointer): DWORD; stdcall;


begin
   Application.ProcessMessages();
   if(dwCallbackReason = CALLBACK_CHUNK_FINISHED) then
      ImageForm.ProgressBar1.Position:= (int64(TotalBytesTransferred) * 100) div int64(TotalFileSize);

   Result:= PROGRESS_CONTINUE;
end;


procedure TImageForm.Button1Click(Sender: TObject);
begin
 Cancel:= false;
  CopyFileEx('\\Sistemas\e\Usuario\Escritorio\catalogo','C:\catalogo1', @ProgressRoutine, nil, @Cancel, 0);
  ShowMessage(SysErrorMessage(GetLastError()));
end;

 procedure TImageForm.Button2Click(Sender: TObject);
begin
Cancel:= true;
end;

end.