diff --git a/README.md b/README.md
index ba20d26..670d16b 100644
--- a/README.md
+++ b/README.md
@@ -36,14 +36,14 @@ return [
     'dot_mail' => [
         'default' => [
             //...
-            'transport' => Symfony\Component\Mailer\Transport\Smtp\SmtpTransport::class,
+            'transport' => 'sendmail',
             //...
         ]
     ]
 ]
 ```
 
-### Mail - SMTP
+### Mail - ESMTP
 
 If you want your application to send mails on e.g. registration, contact, then edit the file `config/autoload/mail.local.php`.  Set the `transport`, `message_options` and `smtp_options` keys like below.
 
@@ -55,7 +55,8 @@ Under `smtp_options` key:
 
 - `host` - the mail server's hostname or IP address
 - `port` - the mail server's port
-- `connection_config` - fill in the `username`, `password` and `ssl` keys with the login details of the email used in `from` above
+- `connection_config` - fill in the `username` and `password` keys with the login details of the email used in `from` above
+- if you want to disable auto_tls set `tls` key to false
 
 Note: all other keys can be left as is.
 
@@ -65,7 +66,7 @@ return [
     'dot_mail' => [
         'default' => [
             //...
-            'transport' => Symfony\Component\Mailer\Transport\Smtp\SmtpTransport::class,
+            'transport' => 'esmtp'
             'message_options' => [
                 'from' => '',
                 //...
@@ -76,7 +77,7 @@ return [
                 'connection_config' => [
                     'username' => '',
                     'password' => '',
-                    'ssl' => '',
+                    'tls' => null,
                 ]
             ]
             //...
diff --git a/config/mail.global.php.dist b/config/mail.global.php.dist
index dcc1a61..9ef3b30 100644
--- a/config/mail.global.php.dist
+++ b/config/mail.global.php.dist
@@ -3,65 +3,37 @@
 declare(strict_types=1);
 
 return [
-
     /**
      * Dotkernel mail module configuration
-     * Note that many of these options can be set programmatically too, when sending mail messages
-     * actually that is what you'll usually do, these config provide just default and options that remain the same for all mails
+     * Note that many of these options can be set programmatically too, when sending mail messages actually that is
+     * what you'll usually do, these configs provide just defaults and options that remain the same for all mails
      */
-
     'dot_mail' => [
-        //the key is the mail service name, this is the default one, which does not extends any configuration
+        //the key is the mail service name, this is the default one, which does not extend any configuration
         'default' => [
-            //tells which other mail service configuration to extend
-            'extends' => null,
-
-            /**
-             * the mail transport to use
-             * can be any class implementing Symfony\Component\Mailer\Transport\TransportInterface
-             *
-             * for standard mail transports, you can use these aliases
-             * - sendmail => Symfony\Component\Mailer\Transport\SendmailTransport
-             * - smtp     => Symfony\Component\Mailer\Transport\Smtp\SmtpTransport
-             *
-             * defaults to sendmail
-             **/
-
-            'transport' => Symfony\Component\Mailer\Transport\SendmailTransport::class,
-
             //message configuration
             'message_options' => [
-
                 //from email address of the email
                 'from' => '',
-
                 //from name to be displayed instead of from address
                 'from_name' => '',
-
                 //reply-to email address of the email
                 'reply_to' => '',
-
                 //replyTo name to be displayed instead of the address
                 'reply_to_name' => '',
-
                 //destination email address as string or a list of email addresses
                 'to' => [],
-
                 //copy destination addresses
                 'cc' => [],
-
                 //hidden copy destination addresses
                 'bcc' => [],
-
                 //email subject
                 'subject' => '',
-
                 //body options - content can be plain text, HTML
                 'body' => [
                     'content' => '',
                     'charset' => 'utf-8',
                 ],
-
                 //attachments config
                 'attachments' => [
                     'files' => [],
@@ -69,45 +41,40 @@ return [
                         'iterate'   => false,
                         'path'      => 'data/mail/attachments',
                         'recursive' => false,
-                    ]
+                    ],
                 ],
             ],
-
-            //options that will be used only if Symfony\Component\Mailer\Transport\Smtp\SmtpTransport adapter is used
+            /**
+             * the mail transport to use can be any class implementing
+             * Symfony\Component\Mailer\Transport\TransportInterface
+             *
+             * for standard mail transports, you can use these aliases:
+             * - sendmail  => Symfony\Component\Mailer\Transport\SendmailTransport
+             * - esmtp     => Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport
+             *
+             * defaults to sendmail
+             **/
+            'transport' => 'sendmail',
+            //options that will be used only if esmtp adapter is used
             'smtp_options' => [
-
                 //hostname or IP address of the mail server
                 'host' => '',
-
                 //port of the mail server - 587 or 465 for secure connections
-                'port' => 587,
-
-                //connection class used for authentication
-                //the value can be one of smtp, plain, login or crammd5
-                'connection_class' => 'login',
-
+                'port'              => 587,
                 'connection_config' => [
-
                     //the smtp authentication identity
                     'username' => '',
-
                     //the smtp authentication credential
                     'password' => '',
-
-                    //the encryption type to be used, ssl or tls
-                    //null should be used to disable SSL
-                    'ssl' => 'tls',
-                ]
+                    //to disable auto_tls set tls key to false
+                    //it's not recommended to disable TLS while connecting to an SMTP server
+                    'tls' => null,
+                ],
             ],
         ],
         // option to log the SENT emails
         'log' => [
-          'sent' => getcwd() . '/log/mail/sent.log'
+            'sent' => getcwd() . '/log/mail/sent.log',
         ],
-
-        /**
-         * You can define other mail services here, with the same structure as the default block
-         * you can even extend from the default block, and overwrite only the differences
-         */
     ],
 ];
diff --git a/docs/book/v5/configuration.md b/docs/book/v5/configuration.md
index 7316366..4c84742 100644
--- a/docs/book/v5/configuration.md
+++ b/docs/book/v5/configuration.md
@@ -21,9 +21,9 @@ $this->mailService->getMessage()->addTo("receiver@email.com");
 ## Transport configuration
 
 `dot-mail` uses the `transport` key under the main `dot_mail` configuration key to select the email transport.
-It has four email transport classes available by default (`SmtpTransport`), one of which is to be added under the `dot_mail.transport` key for use.
+It has two email transport classes available (by default `sendmail`), one of which is to be added under the `dot_mail.transport` key for use.
 
-Sending email with the `Smtp` transport requires valid data for the values under `dot-mail.default.smtp_options`, which is only used in this case.
+Sending email with the `esmtp` transport requires valid data for the values under `dot-mail.default.smtp_options`, which is only used in this case.
 
 > The configured path must be a writable directory
 
diff --git a/docs/book/v5/transports.md b/docs/book/v5/transports.md
index e6301eb..976586f 100644
--- a/docs/book/v5/transports.md
+++ b/docs/book/v5/transports.md
@@ -2,13 +2,13 @@
 
 `dot-mail` can use any transport class that implements `Symfony\Component\Mailer\Transport\TransportInterface`, with the standard transport available being:
 
-- `Symfony\Component\Mailer\Transport\Smtp\SmtpTransport,`
-- `Symfony\Component\Mailer\Transport\SendmailTransport,`
+- `esmtp,`
+- `sendmail,`
 
 > Feel free to use any custom transport you desire, provided it implements the mentioned `TransportInterface`.
 
-PHP's `mail()` function is a wrapper over `Sendmail`, and as such has a different behaviour on Windows than on *nix systems. Using sendmail on Windows **will not work in combination with** `addBcc()`.
+PHP's `mail()` function is a wrapper over `sendmail`, and as such has a different behaviour on Windows than on *nix systems. Using sendmail on Windows **will not work in combination with** `addBcc()`.
 
 - Note: emails sent using the sendmail transport will be more often delivered to SPAM.
 
-`Smtp` connects to the configured SMTP host in order to handle sending emails.
+`esmtp` connects to the configured SMTP host in order to handle sending emails.
diff --git a/src/Factory/MailOptionsAbstractFactory.php b/src/Factory/MailOptionsAbstractFactory.php
index 856ddbf..0d1fb56 100644
--- a/src/Factory/MailOptionsAbstractFactory.php
+++ b/src/Factory/MailOptionsAbstractFactory.php
@@ -5,16 +5,12 @@
 namespace Dot\Mail\Factory;
 
 use Dot\Mail\Options\MailOptions;
-use Laminas\Stdlib\ArrayUtils;
 use Psr\Container\ContainerExceptionInterface;
 use Psr\Container\ContainerInterface;
 use Psr\Container\NotFoundExceptionInterface;
 
-use function array_key_exists;
 use function explode;
 use function is_array;
-use function is_string;
-use function trim;
 
 class MailOptionsAbstractFactory extends AbstractMailFactory
 {
@@ -35,25 +31,6 @@ public function __invoke(ContainerInterface $container, $requestedName, ?array $
             $specificConfig = [];
         }
 
-        /**
-         * Merge any extended mail service config into this one
-         */
-        do {
-            $extendsConfigKey = isset($specificConfig['extends']) && is_string($specificConfig['extends'])
-                ? trim($specificConfig['extends'])
-                : null;
-
-            unset($specificConfig['extends']);
-
-            if (
-                $extendsConfigKey !== null
-                && array_key_exists($extendsConfigKey, $config)
-                && is_array($config[$extendsConfigKey])
-            ) {
-                $specificConfig = ArrayUtils::merge($config[$extendsConfigKey], $specificConfig);
-            }
-        } while ($extendsConfigKey !== null);
-
         return new MailOptions($specificConfig);
     }
 }
diff --git a/src/Factory/MailServiceAbstractFactory.php b/src/Factory/MailServiceAbstractFactory.php
index b3507fd..b03a8d5 100644
--- a/src/Factory/MailServiceAbstractFactory.php
+++ b/src/Factory/MailServiceAbstractFactory.php
@@ -21,7 +21,7 @@
 use RecursiveDirectoryIterator;
 use RecursiveIteratorIterator;
 use Symfony\Component\Mailer\Transport;
-use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
+use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
 use Symfony\Component\Mailer\Transport\TransportInterface;
 
 use function explode;
@@ -177,13 +177,14 @@ protected function createTransport(ContainerInterface $container): TransportInte
 
     protected function setupTransportConfig(TransportInterface $transport): TransportInterface
     {
-        if ($transport instanceof SmtpTransport) {
-            $user = $this->mailOptions->getSmtpOptions()->getConnectionConfig()['username'];
-            $pass = $this->mailOptions->getSmtpOptions()->getConnectionConfig()['password'];
-            $port = $this->mailOptions->getSmtpOptions()->getPort();
-            $host = $this->mailOptions->getSmtpOptions()->getHost();
-
-            $transport = Transport::fromDsn('smtp://' . $user . ':' . $pass . '@' . $host . ':' . $port);
+        if ($transport instanceof EsmtpTransport) {
+            $user      = $this->mailOptions->getSmtpOptions()->getConnectionConfig()['username'];
+            $pass      = $this->mailOptions->getSmtpOptions()->getConnectionConfig()['password'];
+            $tls       = $this->mailOptions->getSmtpOptions()->getConnectionConfig()['tls'] === false ? 'false' : null;
+            $port      = $this->mailOptions->getSmtpOptions()->getPort();
+            $host      = $this->mailOptions->getSmtpOptions()->getHost();
+            $transport = Transport::fromDsn('smtp://' . $user . ':' . $pass . '@' . $host . ':' . $port
+                . '?auto_tls=' . $tls);
         }
 
         return $transport;
diff --git a/src/Options/MailOptions.php b/src/Options/MailOptions.php
index 4e309a1..10153ce 100644
--- a/src/Options/MailOptions.php
+++ b/src/Options/MailOptions.php
@@ -6,7 +6,7 @@
 
 use Laminas\Stdlib\AbstractOptions;
 use Symfony\Component\Mailer\Transport\SendmailTransport;
-use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
+use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
 use Symfony\Component\Mailer\Transport\TransportInterface;
 
 use function array_key_exists;
@@ -21,10 +21,9 @@
 class MailOptions extends AbstractOptions
 {
     protected array $eventListeners                = [];
-    protected array $saveSentMessageFolder         = [];
-    protected TransportInterface|string $transport = SmtpTransport::class;
+    protected TransportInterface|string $transport = EsmtpTransport::class;
     protected array $transportMap                  = [
-        'smtp'     => [SmtpTransport::class],
+        'esmtp'    => [EsmtpTransport::class],
         'sendmail' => [SendmailTransport::class],
     ];
     protected MessageOptions $messageOptions;
@@ -89,14 +88,4 @@ public function setEventListeners(array $eventListeners): void
     {
         $this->eventListeners = $eventListeners;
     }
-
-    public function getSaveSentMessageFolder(): array
-    {
-        return $this->saveSentMessageFolder;
-    }
-
-    public function setSaveSentMessageFolder(array $saveSentMessageFolder): void
-    {
-        $this->saveSentMessageFolder = $saveSentMessageFolder;
-    }
 }
diff --git a/src/Options/SmtpOptions.php b/src/Options/SmtpOptions.php
index db491a7..43f430c 100644
--- a/src/Options/SmtpOptions.php
+++ b/src/Options/SmtpOptions.php
@@ -15,7 +15,6 @@
 class SmtpOptions extends AbstractOptions
 {
     protected string $name            = 'localhost';
-    protected string $connectionClass = 'smtp';
     protected array $connectionConfig = [];
     protected string $host            = '127.0.0.1';
     protected int $port               = 25;
@@ -36,23 +35,6 @@ public function setName(string $name): static
         return $this;
     }
 
-    /**
-     * Get connection class
-     */
-    public function getConnectionClass(): string
-    {
-        return $this->connectionClass;
-    }
-
-    /**
-     * Set connection class
-     */
-    public function setConnectionClass(string $connectionClass): static
-    {
-        $this->connectionClass = $connectionClass;
-        return $this;
-    }
-
     /**
      * Get connection configuration array
      */
diff --git a/test/CommonTrait.php b/test/CommonTrait.php
index 4a21f3b..e42f8f7 100644
--- a/test/CommonTrait.php
+++ b/test/CommonTrait.php
@@ -6,7 +6,6 @@
 
 use org\bovigo\vfs\vfsStream;
 use org\bovigo\vfs\vfsStreamDirectory;
-use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
 
 trait CommonTrait
 {
@@ -46,23 +45,7 @@ private function generateConfig(): array
         return [
             'dot_mail' => [
                 'default' => [
-                    'extends' => null,
-
-                    /**
-                     * the mail transport to use
-                     * can be any class implementing Symfony\Component\Mailer\Transport\TransportInterface
-                     *
-                     * for standard mail transports, you can use these aliases
-                     * - sendmail => Symfony\Component\Mailer\Transport\SendmailTransport
-                     * - smtp     => Symfony\Component\Mailer\Transport\Smtp\SmtpTransport
-                     *
-                     * defaults to sendmail
-                     **/
-                    'transport' => SmtpTransport::class,
-
-                    // Valid only if the Transport is SMTP
-                    'save_sent_message_folder' => ['INBOX.Sent'],
-                    'message_options'          => [
+                    'message_options' => [
                         'from'          => '',
                         'from_name'     => '',
                         'reply_to'      => '',
@@ -84,35 +67,36 @@ private function generateConfig(): array
                             ],
                         ],
                     ],
-
-                    //options that will be used only if Symfony\Component\Mailer\Transport\Smtp\SmtpTransport
+                    /**
+                     * the mail transport to use
+                     * can be any class implementing Symfony\Component\Mailer\Transport\TransportInterface
+                     *
+                     * for standard mail transports, you can use these aliases
+                     * - sendmail => Symfony\Component\Mailer\Transport\SendmailTransport
+                     * - esmtp     => Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport
+                     *
+                     * defaults to sendmail
+                     **/
+                    'transport' => 'esmtp',
+                    //options that will be used only if Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport
                     // adapter is used
                     'smtp_options' => [
                         'host'              => 'testHost',
                         'port'              => 587,
-                        'connection_class'  => 'login',
                         'connection_config' => [
-
                             //the smtp authentication identity
                             'username' => 'test',
-
                             //the smtp authentication credential
                             'password' => 'testPassword',
-                            'ssl'      => 'tls',
+                            'tls'      => null,
                         ],
                     ],
                 ],
                 'test'    => 'string test',
-
                 // option to log the SENT emails
                 'log' => [
                     'sent' => $this->fileSystem->url() . '/log/mail/sent.log',
                 ],
-
-                /**
-                 * You can define other mail services here, with the same structure as the default block
-                 * you can even extend from the default block, and overwrite only the differences
-                 */
             ],
         ];
     }
diff --git a/test/Factory/MailServiceAbstractFactoryTest.php b/test/Factory/MailServiceAbstractFactoryTest.php
index 13565e8..a926bba 100644
--- a/test/Factory/MailServiceAbstractFactoryTest.php
+++ b/test/Factory/MailServiceAbstractFactoryTest.php
@@ -23,7 +23,7 @@
 use Psr\Container\ContainerExceptionInterface;
 use Psr\Container\ContainerInterface;
 use Psr\Container\NotFoundExceptionInterface;
-use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
+use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
 
 class MailServiceAbstractFactoryTest extends TestCase
 {
@@ -91,7 +91,7 @@ public function testGenerateServiceWithProvidedAdapter(): void
             ->willReturn($this->messageOptions);
         $this->mailOptions->expects($this->any())
             ->method('getTransport')
-            ->willReturn($this->createMock(SmtpTransport::class));
+            ->willReturn($this->createMock(EsmtpTransport::class));
         $this->mailOptions->expects($this->any())
             ->method('getEventListeners')
             ->willReturn([AbstractMailEventListener::class]);
@@ -116,7 +116,7 @@ public function testGenerateServiceWithProvidedAdapter(): void
             ->willReturn([
                 'username' => 'test',
                 'password' => 'testPassword',
-                'port'     => 587,
+                'tls'      => null,
             ]);
 
         $this->smtpOptions->expects($this->once())
@@ -129,7 +129,7 @@ public function testGenerateServiceWithProvidedAdapter(): void
 
         $mailService = (new Subject())($this->container, $requestedName);
         $this->assertInstanceOf(MailService::class, $mailService);
-        $this->assertInstanceOf(SmtpTransport::class, $mailService->getTransport());
+        $this->assertInstanceOf(EsmtpTransport::class, $mailService->getTransport());
     }
 
     /**
@@ -159,7 +159,7 @@ public function testGenerateServiceWithoutProvidedAdapter(): void
             ->willReturn($this->messageOptions);
         $this->mailOptions->expects($this->any())
             ->method('getTransport')
-            ->willReturn(SmtpTransport::class);
+            ->willReturn(EsmtpTransport::class);
         $this->mailOptions->expects($this->any())
             ->method('getEventListeners')
             ->willReturn(['Invalid Listener Test']);
@@ -169,13 +169,13 @@ public function testGenerateServiceWithoutProvidedAdapter(): void
             ->willReturnMap([
                 ['dot-mail.options.default', $this->mailOptions],
                 [LogServiceInterface::class, $this->createMock(LogService::class)],
-                [SmtpTransport::class, new SmtpTransport()],
+                [EsmtpTransport::class, new EsmtpTransport()],
                 ['Invalid Listener Test', 'Invalid Listener provided'],
             ]);
         $this->container->expects($this->any())
             ->method('has')
             ->willReturnMap([
-                [SmtpTransport::class, true],
+                [EsmtpTransport::class, true],
                 ['Invalid Listener Test', true],
             ]);
 
@@ -184,7 +184,7 @@ public function testGenerateServiceWithoutProvidedAdapter(): void
             ->willReturn([
                 'username' => 'test',
                 'password' => 'testPassword',
-                'port'     => 587,
+                'tls'      => false,
             ]);
 
         $this->smtpOptions->expects($this->once())
@@ -200,7 +200,7 @@ public function testGenerateServiceWithoutProvidedAdapter(): void
         $mailService = (new Subject())($this->container, $requestedName);
 
         $this->assertInstanceOf(MailService::class, $mailService);
-        $this->assertInstanceOf(SmtpTransport::class, $mailService->getTransport());
+        $this->assertInstanceOf(EsmtpTransport::class, $mailService->getTransport());
         $this->assertCount(2, $mailService->getAttachments());
     }
 
@@ -247,7 +247,7 @@ public function testGenerateServiceThrowException(): void
             ->willReturnMap([
                 ['dot-mail.options.default', $this->mailOptions],
                 [LogServiceInterface::class, $this->createMock(LogService::class)],
-                [SmtpTransport::class, new SmtpTransport()],
+                [EsmtpTransport::class, new EsmtpTransport()],
                 ['Invalid Listener Test', 'Invalid Listener provided'],
             ]);
         $this->container->expects($this->any())
diff --git a/test/Options/MailOptionsTest.php b/test/Options/MailOptionsTest.php
index d20dd3b..5e78703 100644
--- a/test/Options/MailOptionsTest.php
+++ b/test/Options/MailOptionsTest.php
@@ -9,7 +9,7 @@
 use Dot\Mail\Options\MessageOptions;
 use Dot\Mail\Options\SmtpOptions;
 use PHPUnit\Framework\TestCase;
-use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
+use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
 
 class MailOptionsTest extends TestCase
 {
@@ -17,25 +17,22 @@ public function testGettersAndSetters(): void
     {
         $subject = new MailOptions();
 
-        $transport             = 'smtp';
-        $transportMap          = ['test' => 'array'];
-        $messageOptions        = ['from' => '', 'to' => []];
-        $smtpOptions           = ['host' => '', 'port' => 587];
-        $eventListeners        = [AbstractMailEventListener::class];
-        $saveSentMessageFolder = ['INBOX.Sent'];
+        $transport      = 'esmtp';
+        $transportMap   = ['test' => 'array'];
+        $messageOptions = ['from' => '', 'to' => []];
+        $smtpOptions    = ['host' => '', 'port' => 587];
+        $eventListeners = [AbstractMailEventListener::class];
 
         $subject->setTransport($transport);
         $subject->setTransportMap($transportMap);
         $subject->setMessageOptions($messageOptions);
         $subject->setSmtpOptions($smtpOptions);
         $subject->setEventListeners($eventListeners);
-        $subject->setSaveSentMessageFolder($saveSentMessageFolder);
 
-        $this->assertSame(SmtpTransport::class, $subject->getTransport());
+        $this->assertSame(EsmtpTransport::class, $subject->getTransport());
         $this->assertSame($transportMap, $subject->getTransportMap());
         $this->assertInstanceOf(MessageOptions::class, $subject->getMessageOptions());
         $this->assertInstanceOf(SmtpOptions::class, $subject->getSmtpOptions());
         $this->assertSame($eventListeners, $subject->getEventListeners());
-        $this->assertSame($saveSentMessageFolder, $subject->getSaveSentMessageFolder());
     }
 }
diff --git a/test/Options/SmtpOptionsTest.php b/test/Options/SmtpOptionsTest.php
index 3b5bd54..22f7619 100644
--- a/test/Options/SmtpOptionsTest.php
+++ b/test/Options/SmtpOptionsTest.php
@@ -23,7 +23,6 @@ public function testSmtpGettersAndSetters(): void
         $this->assertIsString($subject->getName());
         $this->assertIsArray($subject->getConnectionConfig());
         $this->assertIsString($subject->getHost());
-        $this->assertIsString($subject->getConnectionClass());
         $this->assertIsInt($subject->getPort());
         $this->assertIsInt($subject->getConnectionTimeLimit());
 
diff --git a/test/Service/MailServiceTest.php b/test/Service/MailServiceTest.php
index 02bae60..b87c78a 100644
--- a/test/Service/MailServiceTest.php
+++ b/test/Service/MailServiceTest.php
@@ -17,7 +17,7 @@
 use PHPUnit\Framework\MockObject\Exception;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
-use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
+use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
 use Symfony\Component\Mailer\Transport\TransportInterface;
 use Symfony\Component\Mime\Part\TextPart;
 
@@ -68,7 +68,7 @@ public function setUp(): void
     public function testGettersAndSetters(): void
     {
         $attachments = ['/testAttachment.pdf', '/testDirectory/testAttachment2.xls'];
-        $transport   = $this->createMock(SmtpTransport::class);
+        $transport   = $this->createMock(EsmtpTransport::class);
 
         $this->mailService->setAttachments($attachments);
         $this->mailService->setTransport($transport);