phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO mex2mex_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in) VALUES ('a5295d94164e5f065bf2ba52c38c7a94', -1, 1406667076, 1406667076, '365a7f0a', 7, 0)

Line : 170
File : sessions.php