#0 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Events/SimpleEventDispatcher.php(152): Swift_Plugins_LoggerPlugin->exceptionThrown(Object(Swift_Events_TransportExceptionEvent))
#1 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Events/SimpleEventDispatcher.php(132): Swift_Events_SimpleEventDispatcher->_bubble(Object(Swift_Events_TransportExceptionEvent), 'exceptionThrown')
#2 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(361): Swift_Events_SimpleEventDispatcher->dispatchEvent(Object(Swift_Events_TransportExceptionEvent), 'exceptionThrown')
#3 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(115): Swift_Transport_AbstractSmtpTransport->_throwException(Object(Swift_TransportException))
#4 src/XF/Mail/Mailer.php(274): Swift_Transport_AbstractSmtpTransport->start()
#5 src/XF/Mail/Mail.php(395): XF\Mail\Mailer->send(Object(Swift_Message), Object(Swift_SmtpTransport), NULL, false)
#6 src/XF/Admin/Controller/Tools.php(278): XF\Mail\Mail->send(Object(Swift_SmtpTransport), false)
#7 src/XF/Mvc/Dispatcher.php(321): XF\Admin\Controller\Tools->actionTestEmail(Object(XF\Mvc\ParameterBag))
#8 src/XF/Mvc/Dispatcher.php(248): XF\Mvc\Dispatcher->dispatchClass('XF:Tools', 'TestEmail', Object(XF\Mvc\RouteMatch), Object(XF\Admin\Controller\Tools), NULL)
#9 src/XF/Mvc/Dispatcher.php(100): XF\Mvc\Dispatcher->dispatchFromMatch(Object(XF\Mvc\RouteMatch), Object(XF\Admin\Controller\Tools), NULL)
#10 src/XF/Mvc/Dispatcher.php(50): XF\Mvc\Dispatcher->dispatchLoop(Object(XF\Mvc\RouteMatch))
#11 src/XF/App.php(2177): XF\Mvc\Dispatcher->run()
#12 src/XF.php(390): XF\App->run()
#13 admin.php(13): XF::runApp('XF\\Admin\\App')
#14 {main}