easy way to open docs from asp.net website

create a asp.net page and have on the pageload

            FileInfo fi = new FileInfo(Session["DocName"].ToString());

            if (!fi.Exists)

                return;

            Response.ClearContent();

            Response.ClearHeaders();

            Response.Cache.SetExpires(DateTime.Now.AddSeconds(-1));

            Response.ContentType = "application/download";

            Response.AddHeader("Content-Disposition", "attachment; filename=" + fi.Name);

            Response.AddHeader("Content-Length", fi.Length.ToString());

            Response.WriteFile(Session["DocName"].ToString());

            Response.End();

on your asp page have code thus

         Session["DocName"] = @"c:\blah\blah.xlsx";

            string iframeID = "iframe_contentview";

            string iframe = string.Format("<iframe id=\"{0}\" src=\"{1}\" style=\"display:none\"></iframe>", iframeID, "doc.aspx");

            ClientScript.RegisterStartupScript(GetType(), iframeID, iframe); 

and that's it 

presto!