Support intro
Sorry to hear you’re facing problems 
help.nextcloud.com is for home/non-enterprise users. If you’re running a business, paid support can be accessed via portal.nextcloud.com 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:
example
Or for longer, use three backticks above and below the code snippet:
longer
example
here
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 
Nextcloud version (eg, 20.0.5): 17.0.1
Operating system and version (eg, Ubuntu 20.04): 18.04
Apache or nginx version (eg, Apache 2.4.25): Apache/2.4.29 (Ubuntu)
PHP version (eg, 7.4): PHP 7.2.24
The issue you are facing:
Is this the first time you’ve seen this error? (Y/N): Y
Steps to replicate it:
- The nextcloud server hosted in on prem server and some of the users can’t open their files (not all files). But it shows the folder path, file name, file size in the WEB UI. But after checking it was noticed that files that are tried to open not the server related to that file path. User has uploaded those files via the web interface. Therfore, users can’t access files either open or download.
The output of your Nextcloud log in Admin > Logging:
[PHP] Error: fopen(/mnt/nextcloud-vol/data/username/files/path/to/files/file_name): failed to open stream: No such file or directory at /var/www/nextcloud/lib/private/Files/Storage/Local.php#301
GET /remote.php/webdav/path/to/files/file%20name from user-ip by username at 2023-12-28T06:18:59+00:00
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
<?php
$CONFIG = array (
'instanceid' => 'xxxxxxxxx',
'passwordsalt' => 'xxxxxxxxxxxxxxx',
'secret' => 'xxxxxxxxxxxxxxxxxxxxx',
'trusted_domains' =>
array (
0 => 'nextcloud.abc.com',
),
'datadirectory' => '/mnt/nextcloud-vol/data',
'dbtype' => 'mysql',
'version' => '17.0.1.1',
'overwrite.cli.url' => 'http://nextcloud.abc.com',
'dbname' => 'nextcloud',
'dbhost' => 'x.x.x.x',
'dbport' => '',
'dbtableprefix' => 'oc_',
'mysql.utf8mb4' => true,
'dbuser' => 'nextcloud',
'dbpassword' => 'db-password',
'log_type' => 'file',
'logfile' => '/mnt/nextcloud-vol/log/nextcloud.log',
'loglevel' => 1,
'installed' => true,
'trusted_proxies' =>
array (
0 => 'x.x.x.x',
),
);