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 (18.0.2): 18.0.2
Operating system and version (eg, Ubuntu 17.04): Ubuntu Linux 18.04.4
Apache or nginx version (eg, Apache 2.4.25): Apache 2.4.29
PHP version (eg, 7.1): 7.2.24
The issue you are facing: update to nc version 18.0.3
Update vorbereiten
Log-Level auf “debug” gesetzt
Wartungsmodus eingeschaltet
Reparaturschritt: Repair MySQL collation
Reparaturinformation: All tables already have the correct collation -> nothing to do
Reparaturschritt: Repair SQLite autoincrement
Reparaturschritt: Copy data from accounts table when migrating from ownCloud
Reparaturschritt: Drop account terms table when migrating from ownCloud
Das Datenbankschema wird aktualisiert
Datenbank aktualisiert
Doctrine\DBAL\Exception\DriverException: An exception occurred while executing ‘ALTER TABLE oc_mail_mailboxes DROP sync_token’: SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes
Is this the first time you’ve seen this error? (Y/N): Y
Steps to replicate it:
The output of your Nextcloud log in Admin > Logging:
PASTE HERE
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
$CONFIG = array (
'instanceid' => 'oc2hunhufqga',
'passwordsalt' => '03yRMunPRZVVW84eHxSIfYjHq2Hs+X',
'secret' => 'fQVHzov9G46ohE4AEQF8s+xYINYMeat1eeW33JJJyWfrE7/c',
'trusted_domains' =>
array (
0 => 'localhost',
1 => '....',
2 => '.....',
3 => '[fe80::1:50]',
4 => '....',
5 => '....',
),
'datadirectory' => '/var/www/nextcloud/data',
'dbtype' => 'mysql',
'version' => '18.0.3.0',
'overwrite.cli.url' => 'https://.../nextcloud',
'dbname' => 'nextcloud',
'dbhost' => 'localhost:5432',
'dbport' => '',
'dbtableprefix' => 'oc_',
'dbuser' => 'nextclouduser',
'dbpassword' => '....',
'installed' => true,
'maintenance' => false,
'theme' => '',
'loglevel' => 2,
'mysql.utf8mb4' => true,
);
The output of your Apache/nginx/system log in /var/log/____:
PASTE HERE