Laravel 5.5 with MySQL 8.0.11: 'sql_mode' can't be set to the value of 'NO_AUTO_CREATE_USER'

your laravel connexion (config / database.php) should be such that:

'mysql' => [        'driver' => 'mysql',        'host' => env('DB_HOST', 'localhost'),        'port' => env('DB_PORT', '3306'),        'database' => env('DB_DATABASE', 'forge'),        'username' => env('DB_USERNAME', 'forge'),        'password' => env('DB_PASSWORD', ''),        'charset' => 'utf8',        'collation' => 'utf8_unicode_ci',        'prefix' => '',        'strict' => true,        'engine' => null,        'modes'  => [            'ONLY_FULL_GROUP_BY',            'STRICT_TRANS_TABLES',            'NO_ZERO_IN_DATE',            'NO_ZERO_DATE',            'ERROR_FOR_DIVISION_BY_ZERO',            'NO_ENGINE_SUBSTITUTION',            ],    ],

Add the following on each of your MySQL connections:

'modes' => [     'ONLY_FULL_GROUP_BY',     'STRICT_TRANS_TABLES',     'NO_ZERO_IN_DATE',     'NO_ZERO_DATE',     'ERROR_FOR_DIVISION_BY_ZERO',     'NO_ENGINE_SUBSTITUTION',],

The next release of Laravel 5.5 will add support for MySQL 8.0: https://github.com/laravel/framework/pull/24038

UPDATE: Laravel 5.5.41 has been released.