Upload file fail,Unknown error during upload

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Or for longer, use three backticks above and below the code snippet:


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Nextcloud version (eg, 20.0.5): 28.0.2
Operating system and version (eg, Ubuntu 20.04): debian12
Apache or nginx version (eg, Apache 2.4.25): apache2.4
PHP version (eg, 7.4): 8.2

The issue you are facing:

Is this the first time you’ve seen this error? (Y/N):N

Steps to replicate it:

  1. upload file ,whether drag or click button
  2. upload progress is stop ,after while next cloud while show alter upload fail ,and Unknown error during upload.
  3. i find ,upload function is not stable,sometime is ok, but more time it doesn’t work.

The output of your Nextcloud log in Admin > Logging:
预期文件大小为 10485760字节,实际从 Nextcloud 客户端读入并写入 Nextcloud 存储空间的大小为 0字节。可能是发送端发生了网络问题,或者是服务器写入存储设备时发生错误。

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):


The output of your Apache/nginx/system log in /var/log/____:



Output errors in nextcloud.log in /var/www/ or as admin user in top right menu, filtering for errors. Use a pastebin service if necessary.


Uploading how?

From the Web UI?

The Desktop client?

One of the mobile clients? (Sounds like maybe Android?)

Please provide client version and and the entries from your Nextcloud Server log from the time period of the upload.

from web ui, windows Edge, and server log :BadRequest
BadRequest, expect file size is 10485760 byte ,in fact is 0 form Nextcloud client and write to Nextcloud storge. perhaps there is problem in network or server write to storage.
i think that NC have changed upload mechanism in new version, and make upload files is not stable,when network situation is not good .