[Bitrix\Main\DB\ConnectionException] 
Mysql connect error [localhost, 127.0.0.1] (400)
/home/bitrix/www/bitrix/modules/main/lib/db/mysqlconnection.php:50
#0: Bitrix\Main\DB\MysqlConnection->connectInternal()
	/home/bitrix/www/bitrix/modules/main/lib/db/mysqlconnection.php:103
#1: Bitrix\Main\DB\MysqlConnection->queryInternal(string, array, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:330
#2: Bitrix\Main\DB\Connection->query(string, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:379
#3: Bitrix\Main\DB\Connection->queryExecute(string)
	/home/bitrix/www/bitrix/php_interface/after_connect_d7.php:3
#4: include(string)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:984
#5: Bitrix\Main\DB\Connection->afterConnected()
	/home/bitrix/www/bitrix/modules/main/lib/db/mysqlconnection.php:64
#6: Bitrix\Main\DB\MysqlConnection->connectInternal()
	/home/bitrix/www/bitrix/modules/main/lib/db/mysqlconnection.php:103
#7: Bitrix\Main\DB\MysqlConnection->queryInternal(string, NULL, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:330
#8: Bitrix\Main\DB\Connection->query(string, NULL, integer, integer)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:358
#9: Bitrix\Main\DB\Connection->queryScalar(string)
	/home/bitrix/www/bitrix/modules/security/lib/session.php:115
#10: Bitrix\Security\SessionTable::lock(string, integer)
	/home/bitrix/www/bitrix/modules/security/classes/general/session_db.php:52
#11: CSecuritySessionDB::read(string)
	
#12: session_start()
	/home/bitrix/www/bitrix/modules/main/include.php:281
#13: require_once(string)
	/home/bitrix/www/bitrix/modules/main/include/prolog_before.php:14
#14: require_once(string)
	/home/bitrix/www/bitrix/modules/main/include/prolog.php:10
#15: require_once(string)
	/home/bitrix/www/bitrix/header.php:1
#16: require(string)
	/home/bitrix/www/content/index.php:2
#17: include_once(string)
	/home/bitrix/www/bitrix/modules/main/include/urlrewrite.php:159
#18: include_once(string)
	/home/bitrix/www/bitrix/urlrewrite.php:2

Fatal error: Uncaught exception 'Bitrix\Main\DB\ConnectionException' with message 'Mysql connect error [localhost, 127.0.0.1]' in /home/bitrix/www/bitrix/modules/main/lib/db/mysqlconnection.php:50 Stack trace: #0 /home/bitrix/www/bitrix/modules/main/lib/data/connection.php(53): Bitrix\Main\DB\MysqlConnection->connectInternal() #1 /home/bitrix/www/bitrix/modules/main/lib/db/mysqlsqlhelper.php(21): Bitrix\Main\Data\Connection->getResource() #2 /home/bitrix/www/bitrix/modules/main/lib/db/sqlhelper.php(523): Bitrix\Main\DB\MysqlSqlHelper->forSql('LU769q7cFk9Qk7W...', NULL) #3 /home/bitrix/www/bitrix/modules/main/lib/orm/fields/stringfield.php(142): Bitrix\Main\DB\SqlHelper->convertToDbString('LU769q7cFk9Qk7W...') #4 /home/bitrix/www/bitrix/modules/main/lib/db/sqlhelper.php(434): Bitrix\Main\ORM\Fields\StringField->convertValueToDb('LU769q7cFk9Qk7W...') #5 /home/bitrix/www/bitrix/modules/main/lib/db/sqlhelper.php(408): Bitrix\Main\DB\SqlHelper->convertToDb('LU769q7cFk9Qk7W...', Object(Bitrix\Main\ORM\Fields\StringField)) #6 /h in /home/bitrix/www/bitrix/modules/main/lib/db/mysqlconnection.php on line 50