PostDataStr= "niv=" + textBoxSerie.Text + "&actions=imprime";
PostDataByte= Encoding.UTF8.GetBytes(PostDataStr);
WebBrowser pagina = new WebBrowser();
pagina.AllowWebBrowserDrop = false;
string AdditionalHeaders = "Content-Type: application/x-www-form-urlencoded" + Environment.NewLine;
pagina.Navigate("https://pagina.mx:8046/repuve/consulta.do?niv=" + textBoxSerie.Text + "&actions=rpv","repuve");
pagina.Navigate("https://pagina.mx:8046/repuve/consulta.do" , "repuve", PostDataByte, AdditionalHeaders);