[RuntimeException] 
Could not start session because headers have already been sent. "/var/www/pages/index.php":1. (0)
/var/www/bitrix/modules/main/lib/Session/Session.php:143
#0: Bitrix\Main\Session\Session->start()
	/var/www/bitrix/modules/main/lib/Session/KernelSessionProxy.php:47
#1: Bitrix\Main\Session\KernelSessionProxy->start()
	/var/www/bitrix/modules/main/include.php:151
#2: require_once(string)
	/var/www/bitrix/modules/main/include/prolog_before.php:19
#3: require_once(string)
	/var/www/bitrix/modules/main/include/prolog.php:10
#4: require_once(string)
	/var/www/bitrix/header.php:2
#5: require_once(string)
	/var/www/pages/index.php:4
#6: include_once(string)
	/var/www/bitrix/modules/main/include/urlrewrite.php:128
#7: require_once(string)
	/var/www/bitrix/modules/main/include/routing_index.php:183
#8: include_once(string)
	/var/www/bitrix/routing_index.php:2
----------