Webdav problems with nextcloud 18

Hi all,

i try to setup duplicati with webdav on a nextcloud 18 server. I setup the connection in duplicati and get everytime this error
Failed to connect: Der Server meldete den Fehlercode 405 (MethodNotAllowed), welcher anzeigt, dass der Server keine WebDAV-Verbindungen akzeptiert.

This means something like the server respond 405, which means, that the server did not accept webdav connections

But if i try it with a other webdav client with the same url, username and password like on duplicati everything is working. So i got no idea what the problem is. Could somebody help me to fix this please?

Duplicati is version on windows 10


After a little try and error i finaly got the write way to set up the address and get a connections to my local nextcloud instance. There i use http which works fine with duplicati.

But if i try to access my remote nextcloud server with https i got everytime this error:
401 not authorized

The server use Let´s encrypt certificate. so i wonder, why the server refussed the connection? Anybody an idea?

Old post but same problem. url hosted by synology, Synology DDNS certificate.
No problem to access from linux but refused by duplicati.
Same error message. Work fine using http.