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Test result for cdkauffmannnextcloud.duckdns.org using http-01

A request to your domain revealed that the web server that responded may be the administrative interface of a modem or router. This can indicate an issue with the port forwarding setup on that modem or router. You may need to reconfigure the device to properly forward traffic to your intended webserver.
The web server that responded identified itself as "micro_httpd", which is a known webserver commonly used by modems/routers.

Submitted Dec 11 07:12:05 2018. Sat in queue for 9ms. Completed in 13s. Show verbose information.