Upload error when using File Drop (upload only) on links

Nextcloud version: 21.0.1
Operating system: CentOS Linux release 8.3.2011 Linux 4.18.0-240.10.1.el8_3.x86_64 x86_64
Webserver: Apache/2.4.37 (centos)
Database: mysql 10.3.27
PHP version: 7.4.15

Hi !
I’m having issue when trying to upload in a folder, as a guest, using a “File drop (upload only)” link
I get “Could not upload” error top right of the screen.
observation : file is actually uploaded in non-groupfolders folders - but I get the error on upload

Steps to replicate it:
1- create folder
2- share link > create a “file drop (upload only)”
3- create new private tab in browser, paste the URL
4- Drop a file (or browse) → Error top right : “Could not upload “…””

The output of your Nextcloud log in Admin > Logging:

[PHP] Error: Error: Cannot modify header information - headers already sent by (output started at /var/www/html/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/html/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691 at <>

  1. <>
    OC\Log\ErrorHandler::onError(2, “Cannot modify h … )”, “/var/www/html/n … p”, 691, {string: "X-Hash … "})
  2. /var/www/html/nextcloud/apps/dav/lib/Connector/Sabre/File.php line 691
    header(“X-Hash-MD5: d41 … e”)
  3. /var/www/html/nextcloud/apps/dav/lib/Connector/Sabre/File.php line 189
    OCA\DAV\Connector\Sabre\File->header(“X-Hash-MD5: d41 … e”)
  4. <>
    OCA\DAV\Connector\Sabre\File->OCA\DAV\Connector\Sabre{closure}("*** sensitive parameters replaced ***")
  5. /var/www/html/nextcloud/lib/private/Files/Stream/HashWrapper.php line 71
    call_user_func(Closure {}, “*** sensitive parameter replaced ***”)
  6. <>
    OC\Files\Stream\HashWrapper->stream_close()
  7. /var/www/html/nextcloud/3rdparty/icewind/streams/src/Wrapper.php line 96
    fclose(null)
  8. /var/www/html/nextcloud/lib/private/Files/Stream/HashWrapper.php line 75
    Icewind\Streams\Wrapper->stream_close()
  9. <>
    OC\Files\Stream\HashWrapper->stream_close()
  10. /var/www/html/nextcloud/3rdparty/icewind/streams/src/Wrapper.php line 96
    fclose(null)
  11. /var/www/html/nextcloud/lib/private/Files/Stream/HashWrapper.php line 75
    Icewind\Streams\Wrapper->stream_close()
  12. /var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php line 321
    OC\Files\Stream\HashWrapper->stream_close()
  13. /var/www/html/nextcloud/apps/dav/appinfo/v1/publicwebdav.php line 113
    Sabre\DAV\Server->exec()
  14. /var/www/html/nextcloud/public.php line 81
    require_once("/var/www/html/n … p")

Disabling activity app as suggested in other threads does NOT work. Please advise on what else I can try

Resolved the issue by disabling the app called “Deleted Files”