No thumbnails for media on external shares

I reported this as a bug, but was quickly dismissed to this forum. Can anyone help with this issue ?

:warning: This issue respects the following points: :warning:

This is a bug, not a question or a configuration/webserver/proxy issue.
This issue is not already reported on Github (I've searched it).
Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
Nextcloud Server is running on 64bit capable CPU, PHP and OS.
I agree to follow Nextcloud's Code of Conduct.

Bug description

When I upload a picture or a video on a local drive, I get a thumbnail. When I upload the same picture or video to an external share, I do not get a thumbnail. Also with preview generator. previews is set to ‘on’ at the external share settings.
This is since the latest version: Nextcloud Hub 4 (26.0.0).
The thumbnails did work in the previous version.
Note that if you have thumbnails generated in a previous version, those thumbnails will still work/be shown. Only new thumbnails do not work/are not shown.
Steps to reproduce

Upload a photo or video either through the app or directly via the browser to an external share.

Expected behavior

I expect the thumbnails to work on local aswell as network drives (external storage).
Installation method

Community Web installer on a VPS or web space
Nextcloud Server version

Operating system

PHP engine version

PHP 8.0
Web server

Database engine version

Is this bug present after an update or on a fresh install?

Updated to a major version (ex. 22.2.3 to 23.0.1)
Are you using the Nextcloud Server Encryption module?

Encryption is Disabled
What user-backends are you using?

Default user-backend (database)

Configuration report

“system”: {
“passwordsalt”: “REMOVED SENSITIVE VALUE”,
“trusted_domains”: [”,
“datadirectory”: “REMOVED SENSITIVE VALUE”,
“dbtype”: “mysql”,
“version”: “”,
“overwrite.cli.url”: “”,
“dbport”: “”,
“dbtableprefix”: “oc_”,
“mysql.utf8mb4”: true,
“installed”: true,
“default_phone_region”: “NL”,
“memcache.local”: “\OC\Memcache\APCu”,
“memcache.distributed”: “\OC\Memcache\Redis”,
“redis”: {
“port”: 6379
“memcache.locking”: “\OC\Memcache\Redis”,
“mail_smtpmode”: “sendmail”,
“mail_sendmailmode”: “smtp”,
“mail_from_address”: “REMOVED SENSITIVE VALUE”,
“enable_previews”: true,
“preview_use_imagick”: true,
“preview_interpolate”: false,
“preview_thread_limit”: 20,
“preview_Movie_path”: “/bin/ffmpeg”,
“enabledPreviewProviders”: [
“”: “stable”,
“maintenance”: false,
“theme”: “”,
“loglevel”: 0,
“data-fingerprint”: “950a059e084d4b81576d6bb5053f6bed”

List of activated Apps


  • activity: 2.18.0
  • bruteforcesettings: 2.6.0
  • calendar: 4.3.2
  • circles: 26.0.0
  • cloud_federation_api: 1.9.0
  • comments: 1.16.0
  • contacts: 5.2.0
  • contactsinteraction: 1.7.0
  • dashboard: 7.6.0
  • dav: 1.25.0
  • federatedfilesharing: 1.16.0
  • federation: 1.16.0
  • files: 1.21.1
  • files_external: 1.18.0
  • files_pdfviewer: 2.7.0
  • files_rightclick: 1.5.0
  • files_sharing: 1.18.0
  • files_trashbin: 1.16.0
  • files_versions: 1.19.1
  • firstrunwizard: 2.15.0
  • logreader: 2.11.0
  • lookup_server_connector: 1.14.0
  • mail: 3.1.0
  • nextcloud_announcements: 1.15.0
  • notifications: 2.14.0
  • oauth2: 1.14.0
  • password_policy: 1.16.0
  • photos: 2.2.0
  • previewgenerator: 5.2.2
  • privacy: 1.10.0
  • provisioning_api: 1.16.0
  • recommendations: 1.5.0
  • related_resources: 1.1.0-alpha1
  • serverinfo: 1.16.0
  • settings: 1.8.0
  • sharebymail: 1.16.0
  • support: 1.9.0
  • survey_client: 1.14.0
  • systemtags: 1.16.0
  • text: 3.7.2
  • theming: 2.1.1
  • twofactor_backupcodes: 1.15.0
  • updatenotification: 1.16.0
  • user_status: 1.6.0
  • viewer: 1.10.0
  • weather_status: 1.6.0
  • workflowengine: 2.8.0
  • admin_audit: 1.16.0
  • deck: 1.9.0 (installed 1.9.0)
  • encryption: 2.14.0
  • suspicious_login: 4.4.0
  • twofactor_totp: 8.0.0-alpha.0
  • user_ldap: 1.16.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

No response
Additional info

No response

Got a link?

Check out this external storage fix that might be relevant. Lots of things coming up when searching nextcloud external thumbnails
Also, there are already quite a few topics that might be helpful; Search results for 'external thumbnails' - Nextcloud community in addition to past reportings on Github for server and photos and preview generation.

Not able to reproduce this issue, so good luck.

Well, obviously I checked all the results already before submitting the bug. And it’s actually a bug, because I have found a workaround.

I have recreated the external share in Nextcloud via the administrator external share settings (not the ‘personal’ external share setting.) After doing that and deleting the personal share setting, thumbnails come up without a hitch.

Must have been something to do with upgrading to the latest version.


I have the same, or similar issue, and my external storages were created with the admin.

Still no solution for me.

I guess most people won’t notice this issue since they are either not using external storage or viewing the thumbnails directly on their OS or app and not in the browser…

Did you already try to recreate the storage in Nexcloud ?