phpBB : Critical Error

Error doing DB query userdata row fetch

DEBUG MODE

SQL Error : 1194 Table 's' is marked as crashed and should be repaired

SELECT u.*, s.* FROM phpbb_sessions s, phpbb_users u WHERE s.session_id = 'fb9c52b9ed3fe2e9e3e7f846827798b9' AND u.user_id = s.session_user_id

Line : 315
File : sessions.php