Internal server error when files are shared with the default group for new accounts

[theosche]

Steps to reproduce

1. Create a new group and set it as default for new accounts in registration app settings
2. Share any file with this group
3. Create an account using the registration interface --> Internal server error
   In nextcloud log:

[index] Erreur: The root directory of the user's files is missing
	GET /apps/files/
	de <ip> par <username> à 7 mai 2026, 16:35:22

Additional information:

• There is actually a directory for "username" in nextcloud_data/
• Trying again to log in to the newly created account still leads to the internal server error, with the same entry in nextcloud logs.
• If I try to "impersonate" the newly created account from the admin panel, then it seems to be fixed. Afterwards I can normally login to the account, without any error.
• I think the problem occured since an update to Nextcloud 33.0.3.
• There is no error if I create an account from the admin panel
• There is no error if I stop sharing files to the default group for new accounts (or if I don't select a default group)

Server configuration

Web server: Apache
Database: Mariadb
PHP version: 8.4
Nextcloud version: 33.0.3.2
Registration app version: 2.9.0
Not sure if it matters: the default app for my instance is "Files" (not dashboard)

List of activated apps

Enabled:
  - activity: 6.0.0
  - analytics: 6.3.1
  - announcementcenter: 7.3.0
  - appointments: 2.7.2
  - bruteforcesettings: 6.0.0
  - calendar: 6.2.3
  - camerarawpreviews: 0.9.0
  - circles: 33.0.0
  - cloud_federation_api: 1.17.0
  - collectives: 4.3.0
  - comments: 1.23.0
  - contacts: 8.4.5
  - contactsinteraction: 1.14.1
  - cookbook: 0.11.6
  - dashboard: 7.13.0
  - dav: 1.36.0
  - deck: 1.17.1
  - event_update_notification: 2.8.0
  - external: 8.0.1
  - federatedfilesharing: 1.23.0
  - federation: 1.23.0
  - files: 2.5.0
  - files_downloadlimit: 5.1.0
  - files_external: 1.25.1
  - files_fulltextsearch: 33.0.0
  - files_linkeditor: 1.1.24
  - files_pdfviewer: 6.0.0
  - files_reminders: 1.6.0
  - files_sharing: 1.25.2
  - files_trashbin: 1.23.0
  - files_versions: 1.26.0
  - forms: 5.2.7
  - fulltextsearch: 33.0.0
  - fulltextsearch_elasticsearch: 33.0.0
  - groupfolders: 21.0.7
  - imageconverter: 2.2.0
  - impersonate: 4.0.0
  - integration_giphy: 2.2.1
  - integration_openstreetmap: 4.1.0
  - integration_overleaf: 2.0.1
  - libresign: 13.2.4
  - logcleaner: 1.4.4
  - logreader: 6.0.0
  - lookup_server_connector: 1.21.0
  - mail: 5.7.14
  - memegen: 2.0.1
  - nextcloud_announcements: 5.0.0
  - notes: 5.0.0
  - notifications: 6.0.0
  - notify_push: 1.3.1
  - oauth2: 1.21.0
  - oidc: 1.16.5
  - password_policy: 5.0.0
  - passwords: 2026.5.20
  - photos: 6.0.0
  - polls: 9.0.7
  - privacy: 5.0.0
  - profile: 1.2.0
  - provisioning_api: 1.23.0
  - quota_warning: 1.23.0
  - recommendations: 6.0.0
  - registration: 2.9.0
  - related_resources: 4.0.0
  - richdocuments: 10.1.3
  - secrets: 3.0.3
  - serverinfo: 5.0.0
  - settings: 1.16.0
  - sharebymail: 1.23.0
  - shiftsnext: 2.10.0
  - side_menu: 5.3.0
  - sketch_picker: 2.4.0
  - spreed: 23.0.4
  - support: 5.0.0
  - survey_client: 5.0.0
  - tasks: 0.17.1
  - text: 7.0.1
  - theming: 2.8.0
  - theming_customcss: 1.20.0
  - twofactor_backupcodes: 1.22.0
  - twofactor_nextcloud_notification: 7.0.0
  - twofactor_totp: 15.0.0
  - updatenotification: 1.23.0
  - user_oidc: 8.10.1
  - user_status: 1.13.0
  - viewer: 6.0.0
  - weather_status: 1.13.0
  - webhook_listeners: 1.5.0
  - welcome: 2.0.0
  - whiteboard: 1.5.7
  - workflowengine: 2.15.0

Nextcloud configuration

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "first.domain.ch",
            "second.domain.ch",
            "localhost"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "skeletondirectory": "",
        "dbtype": "mysql",
        "version": "33.0.3.2",
        "overwrite.cli.url": "https:\/\/first.domain.ch",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "mail_smtpmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauthtype": "LOGIN",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "465",
        "maintenance": false,
        "theme": "",
        "loglevel": 2,
        "has_rebuilt_cache": true,
        "mysql.utf8mb4": true,
        "updater.release.channel": "stable",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "filelocking.enabled": true,
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "timeout": 0,
            "password": "***REMOVED SENSITIVE VALUE***"
        },
        "ldapIgnoreNamingRules": false,
        "maintenance_window_start": 1,
        "mail_sendmailmode": "smtp",
        "default_phone_region": "CH",
        "default_language": "fr",
        "default_locale": "fr_CH",
        "default_timezone": "Europe\/Berlin",
        "defaultapp": "files,dashboard",
        "mail_smtpauth": 1,
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "trashbin_retention_obligation": "auto, 30",
        "htaccess.RewriteBase": "\/",
        "enabledPreviewProviders": [
            "OC\\Preview\\BMP",
            "OC\\Preview\\GIF",
            "OC\\Preview\\JPEG",
            "OC\\Preview\\Krita",
            "OC\\Preview\\MarkDown",
            "OC\\Preview\\MP3",
            "OC\\Preview\\OpenDocument",
            "OC\\Preview\\PNG",
            "OC\\Preview\\TXT",
            "OC\\Preview\\XBitmap",
            "OC\\Preview\\HEIC"
        ],
        "app_install_overwrite": [
            "camerarawpreviews",
            "theming_domain",
            "files_archive"
        ],
        "files.chunked_upload.max_size": 20971520,
        "tempdirectory": "\/var\/www\/nextcloud_data\/.php-tmp",
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "serverid": "0"
    }
}

[tcitworld]

I would need the full stacktrace to see what's the issue. Increase your Nextcloud loglevel and activate debug mode when performing the reproducing steps.

The issue is likely connected to the UserEnabledListener listening to the account created event, such as something we do needing user mount being setup before it's actually done by other listeners, but more information is needed to see how this would be related to the default groups settings.

It's also likely this behavior reveals an issue in Nextcloud itself and not with this app, we'll see.

[theosche]

Here is the full log with increased log level, from the beginning of the registration process (verification email), up to the error: nextcloud.log

I also noticed the bug only occurs if using:
'skeletondirectory' => '',
in config.php
So a workaround for the same behaviour is to set an empty existing directory as skeletondirectory