Hi Pepe and thanks alot for your response.
You were right – the XML-RPC was blocked via my host. I have just activated it, but unfortunately the error still occurs.
I have uninstalled your plugin, disconnected from Jetpack, Google and MC and installed + reconnected everything again and started the installation wizard again from step 1. But still the same error at step 3.
Do you have any more recommendation for me?
Best regards
