Uncaught exception thrown in shutdown function.

PDOException: SQLSTATE[HY000]: General error: 8 attempt to write a readonly database: DELETE FROM {semaphore} WHERE (value = :db_condition_placeholder_0) ; Array ( [:db_condition_placeholder_0] => 109216702663002a530b2893.84681490 ) in lock_release_all() (line 269 of D:\Websites\www.sigildesign.co.za\includes\lock.inc).