[Bug]: 0x800701AA and 0x80070185 resulting in error 404 and not being able to download file thru client

⚠️ This issue respects the following points: ⚠️

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

Bug description

Some random files are not available to query thru "index.php/core/preview?fileId=00161436ocad9kxu2atw&x=96&y=96&a=true" with results of [] which results in those files not being able to download using client.
Apache2 log say it results in 404
192.168.51.1 - "" [31/Jan/2025:18:43:44 +0100] "GET /index.php/core/preview?fileId=00161436ocad9kxu2atw&x=96&y=96&a=true HTTP/1.1" 404 814 "-" "Mozilla/5.0 (Windows) mirall/3.15.3 (build 20250107) (Nextcloud, windows-10.0.22621 ClientArchitecture: x86_64 OsArchitecture: x86_64)"

Files is data folder, file is in database
SELECT * FROM oc_filecache WHERE fileid = '00161436ocad9kxu2atw';

return:
| 161436 | 22 | files/Prezenty dla pilotów/2025/AM010124 TAD.pdf | 6a6a0cfc59b4283f35665c032adb9071 | 161433 | AM010124 TAD.pdf | 8 | 7 | 2769270 | 1735830474 | 1735830474 | 0 | 0 | e6f59e957e31b79afb5c91b61debc343 | 27 |

I store data on mounted path via NFS
cd /mnt/nas/
find . -name "AM010124 TAD.pdf"

file is located: /mnt/nas/a.m/files/Prezenty dla pilotów/2025/AM010124 TAD.pdf

Requesting it this way:
curl -u "administrator:password" -X PROPFIND "https://cloud.FQDN.com/remote.php/dav/files/administrator/Prezenty%20dla%20pilot%C3%B3w/2025/AM010124%20TAD.pdf"

give me this results:

<?xml version="1.0"?>
<d:multistatus xmlns:d="DAV:" xmlns:s="http://sabredav.org/ns" xmlns:oc="http://owncloud.org/ns" xmlns:nc="http://nextcloud.org/ns"><d:response><d:href>/remote.php/dav/files/administrator/Prezenty%20dla%20pilot%c3%b3w/2025/AM010124%20TAD.pdf</d:href><d:propstat><d:prop><d:getlastmodified>Thu, 02 Jan 2025 15:07:54 GMT</d:getlastmodified><d:getcontentlength>2769270</d:getcontentlength><d:resourcetype/><d:getetag>&quot;e6f59e957e31b79afb5c91b61debc343&quot;</d:getetag><d:getcontenttype>application/pdf</d:getcontenttype></d:prop><d:status>HTTP/1.1 200 OK</d:status></d:propstat></d:response></d:multistatus>

I tried file scan:
sudo sudo -c "php /var/www/nextcloud/occ files:scan a.m" www-data -s /bin/bash

returns:

Cannot load Zend OPcache - it was already loaded
Starting scan for user 1 out of 1 (a.m)
+---------+-------+-----+---------+---------+--------+--------------+
| Folders | Files | New | Updated | Removed | Errors | Elapsed time |
+---------+-------+-----+---------+---------+--------+--------------+
| 66      | 426   | 0   | 201     | 0       | 0      | 00:00:03     |
+---------+-------+-----+---------+---------+--------+--------------+

but that didn't help

this issue was present on 29.x and is also present on 30.x

Steps to reproduce

1. this is random but you have to have VFS enabled (because other way you would have those files locally)
2. unable to replicate at-hoc
3. if the error occurs I can only download file thru webui or by "store locally" on client.

Expected behavior

being able to download files that is on nextcloud

Nextcloud Server version

30

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.2

Web server

Apache (supported)

Database engine version

MariaDB

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

Upgraded to a MAJOR version (ex. 31 to 32)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "192.168.51.200",
            "cloud.FQDN.com"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "30.0.5.1",
        "overwrite.cli.url": "https:\/\/cloud.FQDN.com",
        "htaccess.RewriteBase": "\/",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "maintenance_window_start": 1,
        "filelocking.enabled": true,
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 6379,
            "timeout": 0,
            "password": "***REMOVED SENSITIVE VALUE***"
        },
        "default_language": "pl",
        "default_phone_region": "PL",
        "default_timezone": "Europe\/Warsaw",
        "allow_user_to_change_display_name": true,
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpmode": "smtp",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": 1,
        "mail_smtpport": "587",
        "mail_sendmailmode": "smtp",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "skeletondirectory": "\/var\/www\/nextcloud\/core\/skeleton_empty",
        "app_install_overwrite": [
            "files_downloadactivity",
            "files_trackdownloads",
            "ransomware_protection"
        ],
        "maintenance": false,
        "theme": "",
        "loglevel": 2,
        "forbidden_filename_basenames": [
            "con",
            "prn",
            "aux",
            "nul",
            "com0",
            "com1",
            "com2",
            "com3",
            "com4",
            "com5",
            "com6",
            "com7",
            "com8",
            "com9",
            "com\u00b9",
            "com\u00b2",
            "com\u00b3",
            "lpt0",
            "lpt1",
            "lpt2",
            "lpt3",
            "lpt4",
            "lpt5",
            "lpt6",
            "lpt7",
            "lpt8",
            "lpt9",
            "lpt\u00b9",
            "lpt\u00b2",
            "lpt\u00b3"
        ],
        "forbidden_filename_characters": [
            "<",
            ">",
            ":",
            "\"",
            "|",
            "?",
            "*",
            "\\",
            "\/"
        ],
        "forbidden_filename_extensions": [
            " ",
            ".",
            ".filepart",
            ".part"
        ]
    }
}

List of activated Apps

Enabled:
  - activity: 3.0.0
  - admin_audit: 1.20.0
  - calendar: 5.0.9
  - circles: 30.0.0
  - cloud_federation_api: 1.13.0
  - comments: 1.20.1
  - contactsinteraction: 1.11.0
  - dashboard: 7.10.0
  - dav: 1.31.1
  - federatedfilesharing: 1.20.0
  - federation: 1.20.0
  - files: 2.2.0
  - files_accesscontrol: 1.20.1
  - files_downloadlimit: 3.0.0
  - files_pdfviewer: 3.0.0
  - files_reminders: 1.3.0
  - files_sharing: 1.22.0
  - files_trashbin: 1.20.1
  - files_versions: 1.23.0
  - impersonate: 1.17.1
  - logreader: 3.0.0
  - lookup_server_connector: 1.18.0
  - notifications: 3.0.0
  - oauth2: 1.18.1
  - password_policy: 2.0.0
  - photos: 3.0.2
  - privacy: 2.0.0
  - provisioning_api: 1.20.0
  - recommendations: 3.0.0
  - related_resources: 1.5.0
  - serverinfo: 2.0.0
  - settings: 1.13.0
  - sharebymail: 1.20.0
  - text: 4.1.0
  - theming: 2.5.0
  - twofactor_backupcodes: 1.19.0
  - updatenotification: 1.20.0
  - user_status: 1.10.0
  - viewer: 3.0.0
  - weather_status: 1.10.0
  - webhook_listeners: 1.1.0-dev
  - workflowengine: 2.12.0
Disabled:
  - app_api: 4.0.5 (installed 4.0.5)
  - bruteforcesettings: 3.0.0 (installed 3.0.0)
  - encryption: 2.18.0
  - files_external: 1.22.0
  - firstrunwizard: 3.0.0 (installed 3.0.0)
  - groupfolders: 18.0.9 (installed 18.0.9)
  - nextcloud_announcements: 2.0.0 (installed 2.0.0)
  - notes: 4.11.0 (installed 4.11.0)
  - support: 2.0.0 (installed 1.12.0)
  - survey_client: 2.0.0 (installed 2.0.0)
  - suspicious_login: 8.0.0
  - systemtags: 1.20.0 (installed 1.20.0)
  - twofactor_nextcloud_notification: 4.0.0
  - twofactor_totp: 12.0.0-dev
  - user_ldap: 1.21.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

{"reqId":"nj46QBqvbY9g9g1oQmxH","level":0,"time":"2025-01-31T18:54:56+00:00","remoteAddr":"192.168.51.1","user":"--","app":"no app in context","method":"GET","url":"/index.php/core/preview?fileId=00161436ocad9kxu2atw&x=96&y=96&a=true","message":"The loading of lazy AppConfig values have been requested","userAgent":"Mozilla/5.0","version":"30.0.5.1","exception":{"Exception":"RuntimeException","Message":"ignorable exception","Code":0,"Trace":[{"file":"/var/www/nextcloud/lib/private/AppConfig.php","line":1180,"function":"loadConfig","class":"OC\\AppConfig","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppConfig.php","line":100,"function":"loadConfigAll","class":"OC\\AppConfig","type":"->"},{"file":"/var/www/nextcloud/lib/private/AllConfig.php","line":169,"function":"getKeys","class":"OC\\AppConfig","type":"->"},{"file":"/var/www/nextcloud/lib/private/Security/Bruteforce/Throttler.php","line":95,"function":"getAppKeys","class":"OC\\AllConfig","type":"->"},{"file":"/var/www/nextcloud/lib/private/Security/Bruteforce/Throttler.php","line":175,"function":"isBypassListed","class":"OC\\Security\\Bruteforce\\Throttler","type":"->"},{"file":"/var/www/nextcloud/lib/private/Security/Bruteforce/Throttler.php","line":192,"function":"getAttempts","class":"OC\\Security\\Bruteforce\\Throttler","type":"->"},{"file":"/var/www/nextcloud/lib/private/Security/Bruteforce/Throttler.php","line":265,"function":"getDelay","class":"OC\\Security\\Bruteforce\\Throttler","type":"->"},{"file":"/var/www/nextcloud/lib/private/User/Session.php","line":383,"function":"sleepDelayOrThrowOnMax","class":"OC\\Security\\Bruteforce\\Throttler","type":"->"},{"file":"/var/www/nextcloud/lib/private/User/Session.php","line":543,"function":"logClientIn","class":"OC\\User\\Session","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/lib/base.php","line":1088,"function":"tryBasicAuthLogin","class":"OC\\User\\Session","type":"->"},{"file":"/var/www/nextcloud/lib/base.php","line":992,"function":"handleLogin","class":"OC","type":"::"},{"file":"/var/www/nextcloud/index.php","line":24,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/nextcloud/lib/private/AppConfig.php","Line":1194,"message":"The loading of lazy AppConfig values have been requested","exception":{},"CustomMessage":"The loading of lazy AppConfig values have been requested"}}

{"reqId":"cKxEVboPydxpVkNNP4UE","level":3,"time":"2025-01-31T18:44:59+00:00","remoteAddr":"192.168.51.1","user":"administrator","app":"index","method":"GET","url":"/settings/api/apps/media?fileName=https%3A%2F%2Fnextcloud.com%2Fc%2Fuploads%2F2024%2F09%2FNextcloud-Hub-9-1024x576.jpg","message":"Exception thrown: OCP\\Files\\NotFoundException","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0","version":"30.0.5.1","exception":{"Exception":"OCP\\Files\\NotFoundException","Message":"","Code":0,"Trace":[{"file":"/var/www/nextcloud/lib/private/Files/Node/Folder.php","line":81,"function":"getFileInfo","class":"OC\\Files\\Node\\Node","type":"->"},{"file":"/var/www/nextcloud/lib/private/Files/SimpleFS/SimpleFolder.php","line":33,"function":"getDirectoryListing","class":"OC\\Files\\Node\\Folder","type":"->"},{"file":"/var/www/nextcloud/apps/settings/lib/Controller/AppSettingsController.php","line":149,"function":"getDirectoryListing","class":"OC\\Files\\SimpleFS\\SimpleFolder","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":208,"function":"getAppDiscoverMedia","class":"OCA\\Settings\\Controller\\AppSettingsController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":114,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/App.php","line":161,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/Route/Router.php","line":302,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"/var/www/nextcloud/lib/base.php","line":1003,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/nextcloud/index.php","line":24,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/nextcloud/lib/private/Files/Node/Node.php","Line":90,"message":"","exception":{},"CustomMessage":"Exception thrown: OCP\\Files\\NotFoundException"}}
{"reqId":"JJQ5AMLoAPk2mDXBdCAn","level":3,"time":"2025-01-31T18:44:59+00:00","remoteAddr":"192.168.51.1","user":"administrator","app":"index","method":"GET","url":"/settings/api/apps/media?fileName=https%3A%2F%2Fgithub.com%2Fnextcloud%2Ffirstrunwizard%2Fraw%2Fmaster%2Fimg%2FNextcloud.webm","message":"Exception thrown: OCP\\Files\\NotFoundException","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0","version":"30.0.5.1","exception":{"Exception":"OCP\\Files\\NotFoundException","Message":"","Code":0,"Trace":[{"file":"/var/www/nextcloud/lib/private/Files/Node/Folder.php","line":81,"function":"getFileInfo","class":"OC\\Files\\Node\\Node","type":"->"},{"file":"/var/www/nextcloud/lib/private/Files/SimpleFS/SimpleFolder.php","line":33,"function":"getDirectoryListing","class":"OC\\Files\\Node\\Folder","type":"->"},{"file":"/var/www/nextcloud/apps/settings/lib/Controller/AppSettingsController.php","line":149,"function":"getDirectoryListing","class":"OC\\Files\\SimpleFS\\SimpleFolder","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":208,"function":"getAppDiscoverMedia","class":"OCA\\Settings\\Controller\\AppSettingsController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":114,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/App.php","line":161,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/Route/Router.php","line":302,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"/var/www/nextcloud/lib/base.php","line":1003,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/nextcloud/index.php","line":24,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/nextcloud/lib/private/Files/Node/Node.php","Line":90,"message":"","exception":{},"CustomMessage":"Exception thrown: OCP\\Files\\NotFoundException"}}
{"reqId":"yNL1N7K5J25ZvmCX88rT","level":0,"time":"2025-01-31T18:50:44+00:00","remoteAddr":"192.168.51.1","user":"administrator","app":"workflowengine","method":"PROPFIND","url":"/remote.php/dav/files/administrator/","message":"Flow activation: rules were requested for operation Zablokuj dost\u0119p do pliku","userAgent":"Mozilla/5.0 (Windows) mirall/3.15.3 (build 20250107) (Nextcloud, windows-10.0.22621 ClientArchitecture: x86_64 OsArchitecture: x86_64)","version":"30.0.5.1","data":{"app":"workflowengine","level":"0"}}
{"reqId":"QhDQ584AEnchArVFGN9t","level":0,"time":"2025-01-31T18:51:07+00:00","remoteAddr":"192.168.51.1","user":"administrator","app":"workflowengine","method":"PROPFIND","url":"/remote.php/dav/files/administrator/Zlecenia%20dla%20pilot%C3%B3w/2025","message":"Flow activation: rules were requested for operation Zablokuj dost\u0119p do pliku","userAgent":"Mozilla/5.0 (Windows) mirall/3.15.3 (build 20250107) (Nextcloud, windows-10.0.22621 ClientArchitecture: x86_64 OsArchitecture: x86_64)","version":"30.0.5.1","data":{"app":"workflowengine","level":"0"}}

Additional info

https://github.com/nextcloud/desktop/issues/7747

sudo -u www-data php occ security:bruteforce:attempts 192.168.51.1
Cannot load Zend OPcache - it was already loaded
  - bypass-listed: false
  - attempts: 2
  - delay: 400

sudo -u www-data php occ security:bruteforce:reset 192.168.51.1

does not help

Adding my ip to bruteforce-setting list does not help:
Your remote address was identified as "192.168.51.1" and is bypassing brute-force protection.

Start with the index.php/core/preview endpoint and the occ files:scan command described in the report, then investigate the failing file's database entry and mounted NFS path under the VFS setup. Reproduce the intermittent 404 and compare preview, WebDAV, client download, and web UI behavior; done means affected files download successfully through the client.