[TypeError] 
Cannot assign null to property Bitrix\Main\Data\Cache::$initDir of type string (0)
/home/plu5684398/plusworld.ru/docs/bitrix/modules/main/lib/data/cache.php:280
#0: Bitrix\Main\Data\Cache->initCache(string, string, NULL, string)
	/home/plu5684398/plusworld.ru/docs/bitrix/modules/main/lib/data/cache.php:371
#1: Bitrix\Main\Data\Cache->startDataCache(string, string, NULL)
	/home/plu5684398/plusworld.ru/docs/bitrix/modules/main/classes/general/component.php:917
#2: CBitrixComponent->startResultCache(string, array, NULL)
	/home/plu5684398/plusworld.ru/docs/local/components/ituka/filter.letter/component.php:34
#3: include(string)
	/home/plu5684398/plusworld.ru/docs/bitrix/modules/main/classes/general/component.php:615
#4: CBitrixComponent->__includeComponent()
	/home/plu5684398/plusworld.ru/docs/bitrix/modules/main/classes/general/component.php:692
#5: CBitrixComponent->includeComponent(string, array, NULL, boolean)
	/home/plu5684398/plusworld.ru/docs/bitrix/modules/main/classes/general/main.php:1195
#6: CAllMain->IncludeComponent(string, string, array)
	/home/plu5684398/plusworld.ru/docs/dictionary/index.php:18
----------