HTTP OPTIONS https://dav.[…].com/%EF%BF%BCdav/zotero/ failed with 410
Your WebDAV server is responding with a HTTP 410 Gone error.
Note that there appears to be a UTF-8 Object Replacement Character in that URL, which shouldn't be there, so if that URL is working elsewhere you might want to try inputting it again.
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Note that there appears to be a UTF-8 Object Replacement Character in that URL, which shouldn't be there, so if that URL is working elsewhere you might want to try inputting it again.