phpBB : Erro Crítico

Error doing DB query userdata row fetch

DEBUG MODE

SQL Error : 2013 Lost connection to MySQL server during query

SELECT u.*, s.* FROM f_activesessions s, f_activeusers u WHERE s.session_id = 'a9b16cc38f4bed67666cb1c9c89c52d7' AND u.user_id = s.session_user_id

Line : 315
File : sessions.php