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this next cloud installation is encrypted BTW.
Nextcloud version (eg, 10.0.2):12.0.3/ later updated to 12.0.4
Operating system and version (eg, Ubuntu 16.04):Manjarolinux version 3.26.2 on a AMD Ryzen 7 1700x , 64 bit,
Apache or nginx version (eg, Apache 2.4.25): Apache Version 2.4.29
PHP version (eg, 5.6):PHP Version 7.0.22
Is this the first time you’ve seen this error?: yes
Can you reliably replicate it? (If so, please outline steps):
LoL I don’t know, I have to get rid of this first I think, Yes I could probably do it again.
The issue you are facing:Unable to delete files or folders where they have been moved/deleted in the backend server file system Also, sharing from a puplic upload folder.
First, I created a shared upload folder, and using the link on a windows 7 pc, i uploaded some .mp3 files that were between 20-40mb each.
I then tried to share these files using the NextCloud app on my Iphone 7 (nextcloud for ios 2.18.2.00001 Nextcloud server 12.0.3,
I was unable to share the files directly from the app, so I attempted to move the files by clicking select/all hit the + and move, into my music area.
This was unable to work.
it timed out, and I don’t remember the exact error code.
At Home, on my pc, Manjarolinux version 3.26.2 on a AMD Ryzen 7 1700x , 64 bit, and
chromium browserVersion 62.0.3202.94 (Developer Build) (64-bit)
I attempted to move the files using the Next Cloud service. logged in as Admin (my name)
Next I went into the server backend, (on my website, achtps using my cpanel login, and was able to 1. move the files, which the next cloud could not then find,
2 Delete the files off the server, which nextcloud then said were still in the publicly shared folder. However this created the top two errors[Quote]Some files have not passed the integrity check. Further information on how to resolve this issue can be found in our documentation. (List of invalid files… / Rescan…)
The “Strict-Transport-Security” HTTP header is not configured to at least “15552000” seconds. For enhanced security we recommend enabling HSTS as described in our security tips.
No memory cache has been configured. To enhance your performance please configure a memcache if available. Further information can be found in our documentation.
The PHP OPcache is not properly configured. For better performance we recommend to use following settings in the php.ini:
opcache.enable=1
opcache.enable_cli=1
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=10000
opcache.memory_consumption=128
opcache.save_comments=1
opcache.revalidate_freq=1
[/Quote]
The output of your Nextcloud log in Admin > Logging:This is huge as there were about 50 files with duplicates
I edited the amount to show each type of error for clarity.
There were problems with the code integrity check. More information…
Nextcloud Test
App Message Time
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 11:45:43
Error files_external Method Not Allowed December 18, 2017 11:45:43
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 11:45:43
Error PHP unlink(): No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Preview/MP3.php#47 December 18, 2017 11:33:23
Error PHP fopen(/home/server/nextclouddata/myadminname/files/NewFiledrop/file name.mp3): failed to open stream: No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/Local.php#277 December 18, 2017 11:33:23
Error PHP unlink(): No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Preview/MP3.php#47 December 18, 2017 11:33:22
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 11:32:52
Error files_external Method Not Allowed December 18, 2017 11:32:52
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 11:32:52
Error files_external Method Not Allowed December 18, 2017 11:22:17
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 11:22:17
Error PHP unlink(): No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Preview/MP3.php#47 December 18, 2017 11:12:04
Error PHP fopen(/home/server/nextclouddata/myadminname/files/NewFiledrop/My File.mp3): failed to open stream: No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/Local.php#277 December 18, 2017 11:12:04
Error PHP unlink(): No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Preview/MP3.php#47 December 18, 2017 11:12:04
Error PHP fopen(/home/server/nextclouddata/myadminname/files/NewFiledrop/filename.mp3): failed to open stream: No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/Local.php#277 December 18, 2017 11:12:04
Error PHP unlink(): No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Preview/MP3.php#47 December 18, 2017 11:12:00
Error files_external Method Not Allowed December 18, 2017 11:04:47
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop” is locked December 18, 2017 11:03:59
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop” is locked December 18, 2017 11:03:55
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop” is locked December 18, 2017 11:03:37
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 11:02:52
Error files_external Method Not Allowed December 18, 2017 11:02:52
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 11:02:51
Error PHP fopen(/home/server/nextclouddata/myadminname/files/NewFiledrop/67-25 67-1105AM Patience.mp3): failed to open stream: No such file or directory at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/Local.php#277 December 18, 2017 10:21:14
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop/my file.mp3” is locked December 18, 2017 10:20:13
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop/my file.mp3” is locked December 18, 2017 10:20:12
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop/filename.mp3” is locked December 18, 2017 10:20:09
Error index Doctrine\DBAL\DBALException: Failed to connect to the database: An exception occured in driver: SQLSTATE[HY000] [1203] User server_next132 already has more than ‘max_user_connections’ active connections December 18, 2017 10:20:07
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop/6my file.mp3” is locked December 18, 2017 10:20:05
Error files_external Method Not Allowed December 18, 2017 10:08:26
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 10:08:26
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 10:08:25
Error files_external Method Not Allowed December 18, 2017 10:08:25
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 10:08:25
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 10:08:24
Error files_external Method Not Allowed December 18, 2017 10:08:24
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 10:08:24
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 10:08:24
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop” is locked December 18, 2017 10:07:38
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop” is locked December 18, 2017 10:07:37
Fatal webdav OCA\DAV\Connector\Sabre\Exception\FileLocked: “NewFiledrop” is locked December 18, 2017 10:07:35
Error PHP Undefined variable: response at /home/server/public_html/testing/nextcloud/lib/private/Files/Storage/DAV.php#286 December 18, 2017 10:07:33
Error files_external Method Not Allowed December 18, 2017 10:07:33
Error no app in context Sabre\HTTP\ClientHttpException: Method Not Allowed December 18, 2017 10:07:33
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
$CONFIG = array (
‘instanceid’ => ‘octkcrypticn’,
‘passwordsalt’ => ‘lalpassencrypt’,
‘secret’ => ‘vsecretlongthing’,
‘trusted_domains’ =>
array (
0 => ‘mysite’,
1 => ‘dubyadubyadubya.emysite.com’,
),
‘datadirectory’ => ‘/home/emyserver/nextclouddata’,
‘overwrite.cli.url’ => ‘achtps://emyssite.com/testing/nextcloud’,
‘dbtype’ => ‘mysql’,
‘version’ => ‘12.0.4.3’,
‘dbname’ => ‘myserver_next132’,
‘dbhost’ => ‘localhost’,
‘dbport’ => ‘’,
‘dbtableprefix’ => ‘oc_’,
‘dbuser’ => ‘myserver_next132’,
‘dbpassword’ => ‘cryptname.)’,
‘installed’ => true,
‘log_type’ => ‘owncloud’,
‘logfile’ => ‘nextcloud.log’,
‘loglevel’ => ‘3’,
‘logdateformat’ => ‘F d, Y H:i:s’,
‘theme’ => ‘’,
‘maintenance’ => false,
);
The output of your Apache/nginx/system log in /var/log/____: I have no idea where to find this, the only /var/ i could find did not have a log/ attatched to it.
Remember, this information may be requested if it isn’t supplied; for fastest response please provide as much as you can 
Feel free to use a pastebin service, otherwise log files can be indented with 4 spaces on each line to present them in a friendlier way on the forum.