OpenDialog is Not working in .EXE File

Hi,
    I have created one windows application,contains richtextbox and Openfiledialog controls.
    Task : After showing the openfiledialog,I  have to read the selected filename and have to display the filename in richtextbox control.
          I have created this application,everything is working fine in my system.
         when I am trying to execute the .EXE file in my client system,It is showing Opendialog but unable to display the filename in the Richtextbox.After clicking the "OPEN" button in the Filedialog the form is getting stuck(hang up).

         My client system doesn't have the Visual studio,but having the Microsoft.Net 3.5 Service Pack1.

private void GetFileName()
{
    OpenFileDialog1.ShowDialog();
    richTextBox1.Text = OpenFileDialog1.SafeFileName;
}

I don't think,it is problem with OpenFileDialog.

To run the .EXE in another system ,do I need any additional tools along with .Net Framework like supporting DLLS.

Please,help me on this Issue,which is very frustarating.

        Any help would be appreciated.

Thanks,
SunilKumar.V