title: NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9813) error not on all iPhones?
body: <p>one of my apps cannot connect to it's API server. The logged reason is <code>NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9813)</code>. So far no luck on finding why or what, but the most frustrating thing is, that this problem appears on some of my test devices. On other everything is fine. I am using <code>NSURLConnection:sendSynchronousRequest:returningResponse:error:</code>, but after some refactoring and trying with <code>NSURLSessionDataTask:dataTaskWithRequest:completionHandler:</code>, the problem still occurs.
  Also added</p>
  
  <pre><code>- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition, NSURLCredential *credential))completionHandler
  {
      completionHandler(NSURLSessionAuthChallengeUseCredential, [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust]);
  }
  </code></pre>
  
  <p>and still nothing.....</p>
  
  <p>p.s. even though my first problem is duplicate of many others, my main concern is why this error appears only on ONE of my testing devices (after Settings -> General -> Reset it works fine too, but how to tell Apple "please, reset your testing device"?). The other work perfectly fine.</p>