It looks like we're not able to support non-local HTTP servers on iOS due to OS security measures. We're going to disable the ability to specify those in the next version. You'll need to use a different server that supports HTTPS, or proxy the HTTP connection via localhost (but you should use HTTPS if you can).
Debug ID D756569957 when use https https also cannot work in desktop. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.
You need a WebDAV server with a valid signed certificate, not a self-signed one. (The desktop can be configured to trust self-signed certificates, but the iOS app cannot.)
@dstillman I use the a WebDAV server with a valid signed certificate, not a self-signed on,but ia appears that :The operation couldn't be completed.(Zotero.AFResponseError error 1.) Debug id is D1494572562. Zotero version 167
@dstillman, to clarify your comment above, will the iOS app continue to support WebDAV servers on the local network accessed via IP address with HTTP? That setup is currently working for me.
Like @kennethhsu , I can access the IP address of the local LAN normally,(http:192.168.2.2:5005/dav/zotero/) ,but I can't access the external domain name （http://x.i.me:5005/dav/zotero/)switched to Synology nas (but it's normal for desktop Zotero to use Synology domain name, whether it's MAC or win)
@mindennis: As I say above, non-local HTTP connections won't work, and won't be configurable in future versions. You need to use HTTPS or a local HTTP connection.
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https also cannot work in desktop. The certificate is not trusted because the issuer certificate is unknown.
The server might not be sending the appropriate intermediate certificates.
An additional root certificate may need to be imported.
https://forums.zotero.org/discussion/comment/393985/#Comment_393985
@friente: You're not using the latest version.
@kennethhsu: Yes.
@dstillman