How to open word doc and pdf

Hi, In my application i want to open word doc and pdf file for only reading no save option and no need to change content just for reading.please help i tried below coding local its working but in my online srever is not working....(its like popup)

private Word.ApplicationClass WordApp = new Word.ApplicationClass();


if (this.openFileDialog1.ShowDialog() == DialogResult.OK)
{
object fileName = openFileDialog1.FileName;
object readOnly = false;

object isVisible = true;
object missing = System.Reflection.Missing.Value;
WordApp.Visible = true;

Word.Document aDoc = WordApp.Documents.Open(ref fileName, ref missing,ref readOnly, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref isVisible);

aDoc.Activate();

}

 

regards,
muthu.
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