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Support intro

Sorry to hear you’re facing problems :slightly_frowning_face: is for home/non-enterprise users. If you’re running a business, paid support can be accessed via where we can ensure your business keeps running smoothly.

In order to help you as quickly as possible, before clicking Create Topic please provide as much of the below as you can. Feel free to use a pastebin service for logs, otherwise either indent short log examples with four spaces:


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


Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can :heart:

Nextcloud version (eg, 29.0.5): Nextcloud Hub 8 (29.0.3)
Operating system and version (eg, Ubuntu 24.04): Debian 12.6
Apache or nginx version (eg, Apache 2.4.25): nginx 1.26.1
PHP version (eg, 8.3): 8.3.8
Installed via docker image Linuxserver/nextcloud

The issue you are facing:

On File page with grid view, not all preview are shown. It needs multiple refreshes in order to replace all generic icon with actual previews as shown below:

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

Steps to replicate it:

  1. Open a Folder with lots of images
  2. change to grid view.

The output of your Nextcloud log in Admin > Logging:

None relate to the operation with log level warning

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

$CONFIG = array (
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'datadirectory' => '/data',
  'instanceid' => '[removed for security]',
  'passwordsalt' => '[removed for security]',
  'secret' => '[removed for security]',
  'version' => '',
  'overwriteprotocol' => 'https',
  'installed' => true,
  'default_phone_region' => 'GB',
  'maintenance' => false,
  'loglevel' => 0,
  'theme' => '',
  'filelocking.enabled' => 'true',
  'upgrade.disable-web' => true,
  'filesystem_check_changes' => 0,
  'maintenance_window_start' => 1,
  'remember_login_cookie_lifetime' => 2592000,
  'session_lifetime' => 604800,
  'memories.exiftool' => '/config/www/nextcloud/apps/memories/bin-ext/exiftool-amd64-musl',
  'memories.vod.path' => '/config/www/nextcloud/apps/memories/bin-ext/go-vod-amd64',
  'memories.vod.ffmpeg' => '/usr/bin/ffmpeg',
  'memories.vod.ffprobe' => '/usr/bin/ffprobe',
  'memories.gis_type' => 1,
  'memories.db.triggers.fcu' => true,
  'dbtype' => 'mysql',
  'dbname' => 'nextcloud',
  'dbhost' => 'mariadb:3306',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => '[removed for security]',
  'dbpassword' => '[removed for security]',
  'trusted_domains' => 
  array (
    0 => '[removed for security]',
    1 => '[removed for security]',
    2 => '[removed for security]',
    3 => '[removed for security]',
  'trusted_proxies' => 
  array (
    0 => '[removed for security]',
    1 => '[removed for security]',
  'overwrite.cli.url' => '[removed for security]',
  'overwritehost' => '[removed for security]',
  'mail_smtpmode' => 'smtp',
  'mail_smtpsecure' => 'tls',
  'mail_sendmailmode' => 'smtp',
  'mail_from_address' => 'nextcloud',
  'mail_domain' => '[removed for security]',
  'mail_smtpauthtype' => 'LOGIN',
  'mail_smtpauth' => 1,
  'mail_smtphost' => '',
  'mail_smtpport' => '587',
  'mail_smtpname' => '[removed for security]',
  'mail_smtppassword' => '[removed for security]',
  'enable_previews' => true,
  'preview_concurrency_all' => 72,
  'preview_concurrency_new' => 36,
  'preview_max_x' => 4096,
  'preview_max_y' => 4096,
  'jpeg_quality' => 80,
  'preview_max_scale_factor' => 1,
  'preview_max_filesize_image' => 50,
  'preview_max_memory' => 256,
  'enabledPreviewProviders' => 
  array (
    0 => 'OC\\Preview\\BMP',
    1 => 'OC\\Preview\\GIF',
    2 => 'OC\\Preview\\JPEG',
    3 => 'OC\\Preview\\Krita',
    4 => 'OC\\Preview\\MarkDown',
    5 => 'OC\\Preview\\OpenDocument',
    6 => 'OC\\Preview\\PNG',
    7 => 'OC\\Preview\\TXT',
    8 => 'OC\\Preview\\XBitmap',
  'memcache.distributed' => '\\OC\\Memcache\\Redis',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' => 
  array (
    'host' => 'redis',
    'port' => 6379,
    'timeout' => 1.5,

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

You should consider to → speedup preview generation with imaginary ←

→ Here is an easy to follow instruction ←

Much and good luck,

Thanks for your suggestion.

I used to deploy imaginary. However, recently I have found that no call is made to imaginary. Furthermore, I have upgrade the hardware now it seems imagick is quick enough.

Ok, let me give imaginary another try.


I have enabled imaginary again and it is not called from Nextcloud. I have posted it as a new post. Could you please help me out?

[help] Imaginary was not called

No. I am out. You did not mention at any place, that you are using docker images. I use BareMetal install with imaginary as described in that linked explanation and it works as a charme. If you want it to do with docker, why don’t you use aio? There is everything together and it works out of the box.

Much and good luck,

Sorry that I missing to the docker part. The support intro didn’t asked for that. Let me add it back to the origin post.

The main reason why I didn’t use AIO was I started using Nextcloud way before AIO was announced.

The other reason was the convenience of Linuxserver images. It provides more features then the AIO like supporting custom scripts and custom components. For example I have installed nextcloud-inotify for watching changes on external-storages.

Thanks for your link.

I am not sure they are the same issue as there are some generic icons shown on mine but blank on yours. They could be related though.

Problem solved with Nextcloud Hub 8 (29.0.4 RC1)
Debian 12