it shows "the attached files in not avaliable on the WebDAV server.please check that the files has synced on the device where it was added".But I can open it normally on my computer
I see you tried opening 2 attachments. The first one actually returned 404 from your WebDAV server, so that's why you got the error message ("the attached files in not avaliable on the WebDAV server.please check that the files has synced on the device where it was added"). The second one seems to have opened correctly.
Did you try opening the same attachment which gave you the original error?
Did it actually remove the downlaoded attachment and re-download it? I don't see the logs for it. Could you create a quick screen recording and share it here or support@zotero.org please?
Can you try downloading this file manually from your WebDAV and open it? I'd like to know whether the file is not corrupted. It should be stored under https://dav.jianguoyun.com/dav/zotero/TFVUYJ3F.zip
I logged into my Nutstor account，but,it shows "This XML file does not appear to have any style information associated with it. The document tree is shown below."
No, that last screenshot is from a Zotero data directory. That shouldn't be on your WebDAV server at all, unless it's just a backup that you're not using directly. You absolutely cannot have you data directory in a cloud storage folder. If you're doing that, you need to immediately move your data directory out of there, or we can't help you further in these forums.
For the XML from the actual 'zotero' folder created by Zotero WebDAV sync, showing an XML error message for a missing file is fine in principle, but we need to confirm that the server is actually properly returning a 404 error code. Can you open the Developer Tools (View → Developer → Developer Tools), go to the Network tab, and reload the .zip URL, and look at the first line? It should say 404 in the Status column. Can you share a screenshot of that?
It would only be there if you moved it there in the first place by changing the Data Directory setting in the Files and Folders section of the Zotero settings:
(Zotero 7 will look a bit different, but the settings are the same.)
You should change it back to the default location and then move your files there.
That wouldn't actually be related to the issue on the iPad, but as a general rule we can't provide support when people have their data directory in cloud storage, because it can cause all sorts of unexpected breakage.
Upgrade Storage
https://www.zotero.org/support/debug_output#zotero_for_ios
Did you try opening the same attachment which gave you the original error?
Can you try downloading this file manually from your WebDAV and open it? I'd like to know whether the file is not corrupted. It should be stored under https://dav.jianguoyun.com/dav/zotero/TFVUYJ3F.zip
Here is the file I found by logging into the account on the official website
For the XML from the actual 'zotero' folder created by Zotero WebDAV sync, showing an XML error message for a missing file is fine in principle, but we need to confirm that the server is actually properly returning a 404 error code. Can you open the Developer Tools (View → Developer → Developer Tools), go to the Network tab, and reload the .zip URL, and look at the first line? It should say 404 in the Status column. Can you share a screenshot of that?
https://www.zotero.org/support/preferences/advanced#files_and_folders
(Zotero 7 will look a bit different, but the settings are the same.)
You should change it back to the default location and then move your files there.
That wouldn't actually be related to the issue on the iPad, but as a general rule we can't provide support when people have their data directory in cloud storage, because it can cause all sorts of unexpected breakage.