diff --git a/.env b/.env
index d2e7ef0..c5d1f43 100644
--- a/.env
+++ b/.env
@@ -20,5 +20,5 @@ APP_SECRET=7d51ea8178822362dc294317d8223d23
 #TRUSTED_HOSTS='^localhost|example\.com$'
 ###< symfony/framework-bundle ###
 ###> symfony/mailer ###
-MAILER_DSN=sendmail://localhost
+MAILER_DSN=null://null
 ###< symfony/mailer ###
diff --git a/config/services.yaml b/config/services.yaml
index 0086b1d..73e6296 100644
--- a/config/services.yaml
+++ b/config/services.yaml
@@ -20,6 +20,9 @@ services:
     resource: '../src/*'
     exclude: '../src/{DependencyInjection,Entity,Migrations,Model,Platform/Platform.php,Tests,Kernel.php}'
 
+  console.command.mailer_test:
+    class: Mfc\PasswordManager\Command\MailerTestCommand
+
 #  Symfony\Component\Mailer\MailerInterface:
 #    factory: ['@Mfc\PasswordManager\Services\Mail\MailerFactory', 'buildMailer']
 #    lazy: true
diff --git a/examples/config.yaml b/examples/config.yaml
index 50a18cc..12a76cd 100644
--- a/examples/config.yaml
+++ b/examples/config.yaml
@@ -1,6 +1,6 @@
 mfc_password_manager:
   mail:
-    dsn: "smtp://srelay-int.web-factory.de"
+    dsn: "smtp://srelay-ext.web-factory.de:25?verify_peer=false"
   database:
     default_credentials:
       username: db_pusher_user
diff --git a/src/Command/MailerTestCommand.php b/src/Command/MailerTestCommand.php
new file mode 100644
index 0000000..74aa210
--- /dev/null
+++ b/src/Command/MailerTestCommand.php
@@ -0,0 +1,81 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Mfc\PasswordManager\Command;
+
+use Mfc\PasswordManager\Services\ConfigurationService;
+use Mfc\PasswordManager\Services\Mail\MailerFactory;
+use Symfony\Component\Console\Attribute\AsCommand;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Mime\Email;
+
+/**
+ * A console command to test Mailer transports.
+ */
+#[AsCommand(name: 'mailer:test', description: 'Test Mailer transports by sending an email')]
+final class MailerTestCommand extends Command
+{
+    use ConfigDirectoryTrait;
+
+    public function __construct(
+        private readonly ConfigurationService $configurationService,
+        private readonly MailerFactory $mailerFactory
+    ) {
+        parent::__construct();
+    }
+
+    protected function configure(): void
+    {
+        $this
+            ->addArgument('to', InputArgument::REQUIRED, 'The recipient of the message')
+            ->addOption('from', null, InputOption::VALUE_OPTIONAL, 'The sender of the message', 'from@example.org')
+            ->addOption('subject', null, InputOption::VALUE_OPTIONAL, 'The subject of the message', 'Testing transport')
+            ->addOption('body', null, InputOption::VALUE_OPTIONAL, 'The body of the message', 'Testing body')
+            ->addOption('transport', null, InputOption::VALUE_OPTIONAL, 'The transport to be used')
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command tests a Mailer transport by sending a simple email message:
+
+<info>php %command.full_name% to@example.com</info>
+
+You can also specify a specific transport:
+
+    <info>php %command.full_name% to@example.com --transport=transport_name</info>
+
+Note that this command bypasses the Messenger bus if configured.
+
+EOF
+            )
+            ->configureConfigDirectory();
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $this->loadConfiguration($this->configurationService, $input);
+
+        $message = (new Email())
+            ->to($input->getArgument('to'))
+            ->from($input->getOption('from'))
+            ->subject($input->getOption('subject'))
+            ->text($input->getOption('body'));
+        if ($transport = $input->getOption('transport')) {
+            $message->getHeaders()->addTextHeader('X-Transport', $transport);
+        }
+
+        $mailer = $this->mailerFactory->buildMailer();
+        $mailer->send($message);
+
+        return 0;
+    }
+}
diff --git a/src/Services/UserStorage.php b/src/Services/UserStorage.php
index 5ff3c4b..f03c808 100644
--- a/src/Services/UserStorage.php
+++ b/src/Services/UserStorage.php
@@ -11,11 +11,11 @@
 use Mfc\PasswordManager\Security\Encoder\Md5PasswordEncoder;
 use Mfc\PasswordManager\Security\Encoder\PasswordEncoderInterface;
 use Mfc\PasswordManager\Security\Encoder\Sha1PasswordEncoder;
+use Mfc\PasswordManager\Services\Mail\MailerFactory;
 use Psr\Log\LoggerInterface;
 use Symfony\Bridge\Twig\Mime\NotificationEmail;
 use Symfony\Component\Finder\Finder;
 use Symfony\Component\Finder\SplFileInfo;
-use Symfony\Component\Mailer\MailerInterface;
 use Symfony\Component\Mime\Address;
 use Symfony\Component\Serializer\SerializerInterface;
 use Symfony\Component\Yaml\Yaml;
@@ -45,8 +45,8 @@ class UserStorage
      */
     public function __construct(
         private ConfigurationService $configurationService,
+        private readonly MailerFactory $mailerFactory,
         private readonly SerializerInterface $serializer,
-        private readonly MailerInterface $mailer,
         private readonly LoggerInterface $logger
     ) {
     }
@@ -214,7 +214,8 @@ private function sendPlainPasswordToUser(User $user, string $plainPassword): voi
             )
             ->importance(NotificationEmail::IMPORTANCE_HIGH);
 
-        $this->mailer->send($email);
+        $mailer = $this->mailerFactory->buildMailer();
+        $mailer->send($email);
     }
 
     public function enableDryRun(): self