asp.net mvc c# Request.Files[0].ContentLength getting zero internet explorer

Question

The file size validation is not working in Internet Explorer, it worked fine in FireFox. It is posting at octet in Internet Explorer, what could be the reason?

Session["ContentLength"] = (Request.Files[0].ContentLength / 1024);
Session["ContentType"] = Request.Files[0].ContentType;
byte[] b = new byte[Request.Files[0].ContentLength];
Request.Files[0].InputStream.Read(b, 0, Request.Files[0].ContentLength);
Session["ContentStream"] = b;
return Content(Request.Files[0].ContentType + ";" + Request.Files[0].ContentLength / 1024);