Urgent – Folder upload failing with 404 error (WebDAV / CIFS storage)

We are experiencing a critical issue following a Nextcloud upgrade.

Issue description:

  • Uploading single files works correctly

  • Uploading folders via drag & drop fails

  • Error message: “The target folder no longer exists”

  • From browser developer tools:

    • PUT /remote.php/dav/… → 404 Not Found
  • Behavior observed:

    • The folder is created in the parent directory

    • But the files inside the folder are not uploaded

Additional details:

  • Upload works when dropping into the root directory

  • The issue only occurs when uploading into a subfolder

Environment:

  • Nextcloud version: 33.0.0 (previously 32.x)

  • Storage: CIFS network share (NAS)

  • Datadirectory is located on this mounted share

Permissions:

We have verified that:

  • The web server user (www-data) has full read/write permissions on the storage

  • Manual file and folder creation from the server works without any issue

Request:

Could you please advise:

  • If this issue is known with WebDAV and/or CIFS storage

  • If there is any recommended configuration or fix

  • Or if this could be related to caching or permission handling

This issue is impacting production usage, so your prompt assistance would be greatly appreciated.