HttpClient.get() fails with -1

Using Arduino Networking, Protocols, and Devices
1

I'm programming my ESP32 with the ArduinoIDE and have a problem with HTTP GET. What I'm doing:

  • the ESP32 connects as WiFi client to an existing WiFi network using a static, fixed IP

  • a webserver is started which provides a webpage for OTA firmware update -> this works, the webpage is accessible via the static IP

  • using HttpClient I try to GET an other, remote webserver, but this fails

This is the code I'm using for the HTTP GET call:

static WiFiClient wifi;

HttpClient wlanHttp=HttpClient(wifi,"my.server.tld");
wlanHttp.get("/setpos.php?id=DEADBEEF"); // -> this fails with error code -1
wlanHttp.responseStatusCode(); // follow-up error -1
wlanHttp.stop();

Any idea what goes wrong here?

Thanks!