Joomla Admin Error Code 2 SMTP

ik kan geen error code 2 vinden in de logs. 
wel in depreciated. phph onzettrnd veel warnings
en in full.php ook - wellicht door dat we nog op 5.34 draaien, pending update van Easyblog issue

Eindelijk - een log entry

2025-11-27T15:32:23+00:00    CRITICAL 94.214.3.213    error    Uncaught Throwable of type PHPMailer\PHPMailer\Exception thrown with message "SMTP Error: data not accepted.". Stack trace: #0 [ROOT]/libraries/vendor/phpmailer/phpmailer/src/PHPMailer.php(1687): PHPMailer\PHPMailer\PHPMailer->smtpSend()
#1 [ROOT]/libraries/vendor/phpmailer/phpmailer/src/PHPMailer.php(1521): PHPMailer\PHPMailer\PHPMailer->postSend()
#2 [ROOT]/libraries/src/Mail/Mail.php(172): PHPMailer\PHPMailer\PHPMailer->send()
#3 [ROOT]/plugins/authentication/akeeba/src/Extension/Akeeba.php(96): Joomla\CMS\Mail\Mail->Send()
#4 [ROOT]/libraries/src/Plugin/CMSPlugin.php(311): Joomla\Plugin\Authentication\Akeeba\Extension\Akeeba->onUserAuthenticate()
#5 [ROOT]/libraries/vendor/joomla/event/src/Dispatcher.php(454): Joomla\CMS\Plugin\CMSPlugin->Joomla\CMS\Plugin\{closure}()
#6 [ROOT]/libraries/src/Authentication/Authentication.php(162): Joomla\Event\Dispatcher->dispatch()
#7 [ROOT]/libraries/src/Application/CMSApplication.php(893): Joomla\CMS\Authentication\Authentication->authenticate()
#8 [ROOT]/libraries/src/Application/AdministratorApplication.php(360): Joomla\CMS\Application\CMSApplication->login()
#9 [ROOT]/administrator/components/com_login/src/Controller/DisplayController.php(83): Joomla\CMS\Application\AdministratorApplication->login()
#10 [ROOT]/libraries/src/MVC/Controller/BaseController.php(730): Joomla\Component\Login\Administrator\Controller\DisplayController->login()
#11 [ROOT]/libraries/src/Dispatcher/ComponentDispatcher.php(143): Joomla\CMS\MVC\Controller\BaseController->execute()
#12 [ROOT]/administrator/components/com_login/src/Dispatcher/Dispatcher.php(45): Joomla\CMS\Dispatcher\ComponentDispatcher->dispatch()
#13 [ROOT]/libraries/src/Component/ComponentHelper.php(361): Joomla\Component\Login\Administrator\Dispatcher\Dispatcher->dispatch()
#14 [ROOT]/libraries/src/Application/AdministratorApplication.php(150): Joomla\CMS\Component\ComponentHelper::renderComponent()
#15 [ROOT]/libraries/src/Application/AdministratorApplication.php(205): Joomla\CMS\Application\AdministratorApplication->dispatch()
#16 [ROOT]/libraries/src/Application/CMSApplication.php(304): Joomla\CMS\Application\AdministratorApplication->doExecute()
#17 [ROOT]/administrator/includes/app.php(58): Joomla\CMS\Application\CMSApplication->execute()
#18 [ROOT]/administrator/index.php(32): require_once('/home/malawit1/...')