// Instantiates http web client with cookie header from login
 private void InitWebClient(string cookieHeader)
 {
     CookieContainer cookieJar = new CookieContainer();
     cookieJar.SetCookies(new Uri(PORTAL + "/webapps/login/"), cookieHeader);
     http = new WebClientEx(cookieJar);
     initialized = true;
 }