My apologies if I have posted in the incorrect forum. I am writing an application in the Zend Framework and have just made the switch from a mySql database to Oracle. I am getting this error immediately when I try to use the login function on the application. Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[HY000]: pdo_oci_handle_factory: ORA-12537: TNS:connection closed (ext\pdo_oci\oci_driver.c:579)' Any help would be greatly appreciated! Thanks.