Is there a way I could run it in background. i.e. without opening the word file.

Have manage to read the contents but it one can certainly notice the opening and closing of the world doc

Microsoft.Office.Interop.Word.Application wordApp = new Microsoft.Office.Interop.Word.ApplicationClass();

object fileNameO = fileName;//"c:\\sample.doc";
object objFalse = false;
object objTrue = true;
object missing = System.Reflection.Missing.Value;
object emptyData = string.Empty;

try
{
Microsoft.Office.Interop.Word.Document aDoc = wordApp.Documents.Open(ref fileNameO, ref objFalse, ref objTrue,
ref objFalse, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref objTrue,
ref missing, ref missing, ref missing, ref missing);

aDoc.ActiveWindow.Selection.WholeStory();
aDoc.ActiveWindow.Selection.Copy();


IDataObject data = System.Windows.Forms.Clipboard.GetDataObject();
String filetext = data.GetData(System.Windows.Forms.DataFormats.Text).ToString();
System.Windows.Forms.Clipboard.SetDataObject(string.Empty);
richTextBox1.Text = filetext;
}
catch (Exception err)
{
MessageBox.Show(err.Message);
}
finally
{
wordApp.Documents.Close(ref missing, ref missing, ref missing);
wordApp.Application.Quit(ref missing, ref missing, ref missing);
}
}