diff --git a/Classes/Controller/NewsletterController.php b/Classes/Controller/NewsletterController.php
index f06eaba..beca92d 100644
--- a/Classes/Controller/NewsletterController.php
+++ b/Classes/Controller/NewsletterController.php
@@ -11,6 +11,7 @@
 use In2code\Luxletter\Domain\Service\PreviewUrlService;
 use In2code\Luxletter\Domain\Service\QueueService;
 use In2code\Luxletter\Domain\Service\ReceiverAnalysisService;
+use In2code\Luxletter\Events\AfterTestMailButtonClickedEvent;
 use In2code\Luxletter\Exception\AuthenticationFailedException;
 use In2code\Luxletter\Mail\TestMail;
 use In2code\Luxletter\Utility\BackendUserUtility;
@@ -225,16 +226,43 @@ public function testMailAjax(ServerRequestInterface $request): ResponseInterface
         if (BackendUserUtility::isBackendUserAuthenticated() === false) {
             throw new AuthenticationFailedException('You are not authenticated to send mails', 1560872725);
         }
-        $testMail = GeneralUtility::makeInstance(TestMail::class);
-        $status = $testMail->preflight(
-            $request->getQueryParams()['origin'],
-            $request->getQueryParams()['layout'],
-            (int)$request->getQueryParams()['configuration'],
-            $request->getQueryParams()['subject'],
-            $request->getQueryParams()['email']
-        );
+        $status = null;
+
+        /**
+         * This event can be used for sending the Testemail with external logic
+         * @see Documentation/Tech/Events.md
+         */
+        /** @var AfterTestMailButtonClickedEvent $event */
+        $event = GeneralUtility::makeInstance(AfterTestMailButtonClickedEvent::class);
+        $event->setRequest($request);
+        $this->eventDispatcher->dispatch($event);
+
+        if (!$event->isTestMailIsSendExternal()) {
+            $testMail = GeneralUtility::makeInstance(TestMail::class);
+            $status = $testMail->preflight(
+                $request->getQueryParams()['origin'],
+                $request->getQueryParams()['layout'],
+                (int)$request->getQueryParams()['configuration'],
+                $request->getQueryParams()['subject'],
+                $request->getQueryParams()['email']
+            );
+        }
+        $event->setTestMailIsSendExternal(true);
         $response = ObjectUtility::getJsonResponse();
-        $response->getBody()->write(json_encode(['status' => $status]));
+        $responseData = [
+            'status' => $status ?? $event->getStatus(),
+        ];
+        if ($event->isTestMailIsSendExternal()){
+            $responseData = array_merge(
+                $responseData,
+                [
+                    'statusTitle' => $event->getStatusTitle(),
+                    'statusMessage' => $event->getStatusMessage(),
+                    'statusSeverity' => $event->getStatusSeverity(),
+                ]
+            );
+        }
+        $response->getBody()->write(json_encode($responseData, JSON_THROW_ON_ERROR));
         return $response;
     }
 
@@ -261,8 +289,10 @@ public function receiverDetailAjax(ServerRequestInterface $request): ResponseInt
         $standaloneView->assignMultiple([
             'user' => $user,
             'visitor' => $visitorRepository->findOneByFrontenduser($user),
-            'logs' => $logRepository->findByUser($user),
         ]);
+        if ($user !== null) {
+            $standaloneView->assign('logs', $logRepository->findByUser($user));
+        }
         $response = ObjectUtility::getJsonResponse();
         $response->getBody()->write(json_encode(
             ['html' => $standaloneView->render()]
diff --git a/Classes/Events/AfterTestMailButtonClickedEvent.php b/Classes/Events/AfterTestMailButtonClickedEvent.php
new file mode 100644
index 0000000..b489ca8
--- /dev/null
+++ b/Classes/Events/AfterTestMailButtonClickedEvent.php
@@ -0,0 +1,85 @@
+<?php
+
+declare(strict_types=1);
+namespace In2code\Luxletter\Events;
+
+use Psr\Http\Message\ServerRequestInterface;
+
+final class AfterTestMailButtonClickedEvent
+{
+    const STATUS_SEVERITY_SUCCESS = 'alert-success';
+    const STATUS_SEVERITY_WARNING = 'alert-warning';
+    const STATUS_SEVERITY_ERROR = 'alert-danger';
+
+    protected bool $testMailIsSendExternal = false;
+
+    protected bool $status = false;
+
+    protected string $statusTitle = '';
+
+    protected string $statusMessage = '';
+
+    protected string $statusSeverity = self::STATUS_SEVERITY_ERROR;
+
+    protected ServerRequestInterface $request;
+
+    public function isTestMailIsSendExternal(): bool
+    {
+        return $this->testMailIsSendExternal;
+    }
+
+    public function setTestMailIsSendExternal(bool $testMailIsSendExternal): void
+    {
+        $this->testMailIsSendExternal = $testMailIsSendExternal;
+    }
+
+    public function getStatus(): bool
+    {
+        return $this->status;
+    }
+
+    public function setStatus(bool $status): void
+    {
+        $this->status = $status;
+    }
+
+    public function getRequest(): ServerRequestInterface
+    {
+        return $this->request;
+    }
+
+    public function setRequest(ServerRequestInterface $request): void
+    {
+        $this->request = $request;
+    }
+
+    public function getStatusTitle(): string
+    {
+        return $this->statusTitle;
+    }
+
+    public function setStatusTitle(string $statusTitle): void
+    {
+        $this->statusTitle = $statusTitle;
+    }
+
+    public function getStatusMessage(): string
+    {
+        return $this->statusMessage;
+    }
+
+    public function setStatusMessage(string $statusMessage): void
+    {
+        $this->statusMessage = $statusMessage;
+    }
+
+    public function getStatusSeverity(): string
+    {
+        return $this->statusSeverity;
+    }
+
+    public function setStatusSeverity(string $statusSeverity): void
+    {
+        $this->statusSeverity = $statusSeverity;
+    }
+}
diff --git a/Documentation/Tech/Events.md b/Documentation/Tech/Events.md
new file mode 100644
index 0000000..0bb725e
--- /dev/null
+++ b/Documentation/Tech/Events.md
@@ -0,0 +1,43 @@
+<img align="left" src="../../Resources/Public/Icons/lux.svg" width="50" />
+
+# Luxletter - Email marketing in TYPO3. Send newsletters the easy way.
+
+## Events
+
+There are many events that can be used to extend Luxletter.
+This documentation is under construction and not all events are documented yet.
+
+### AfterTestMailButtonClickedEvent
+
+This event can be used to deactivate the internal sending of test emails and implement your own logic, e.g. sending test newsletters via a separate queue.
+
+To deactivate the internal logic, the `$testMailIsSendExternal` property of the event must be set to true.
+If the general status `$status` is set to `false`, no message is shown.
+If the general status `$status` is set to `true`, a message with the properties `$statusTitle`, `$statusMessage` and `$statusSeverity` is shown.
+The values for `$statusSeverity` can be `AfterTestMailButtonClickedEvent::STATUS_SEVERITY_SUCCESS`, `AfterTestMailButtonClickedEvent::STATUS_SEVERITY_WARNING` and `AfterTestMailButtonClickedEvent::STATUS_SEVERITY_ERROR`, the default value is `AfterTestMailButtonClickedEvent::STATUS_SEVERITY_ERROR`.
+
+The `$request` property is available in the event, from which all necessary data can be obtained to send the test e-mail.
+
+Sample Eventlistener:
+
+```
+<?php
+
+declare(strict_types=1);
+namespace Vendor\Extension\EventListener;
+
+use In2code\Luxletter\Events\AfterTestMailButtonClickedEvent;
+
+final class DemoEventlistener
+{
+    public function __invoke(AfterTestMailButtonClickedEvent $event): void
+    {
+        $event->setTestMailIsSendExternal(true);
+        // ... handle email sending
+        $event->setStatus(true);
+        $event->setStatusSeverity(AfterTestMailButtonClickedEvent::STATUS_SEVERITY_SUCCESS);
+        $event->setStatusTitle('Success');
+        $event->setStatusMessage('The test email is successfully added to the queue');
+    }
+}
+```
diff --git a/Resources/Private/Build/JavaScript/Module.js b/Resources/Private/Build/JavaScript/Module.js
index 2fd8131..7c849d2 100644
--- a/Resources/Private/Build/JavaScript/Module.js
+++ b/Resources/Private/Build/JavaScript/Module.js
@@ -265,13 +265,19 @@ define(['jquery'], function($) {
      */
     this.testMailListenerCallback = function(response) {
       const messageElement = document.querySelector('[data-luxletter-testmail="message"]');
-      if (messageElement !== null && response.status === true) {
+      if (messageElement !== null && response.statusSeverity === undefined && response.status === true) {
         showElement(messageElement);
 
         const counterElement = messageElement.querySelector('p>span');
         let counter = parseInt(counterElement.innerHTML);
         counter++;
         counterElement.innerHTML = counter.toString();
+      } else if(messageElement !== null && response.statusSeverity !== '' && response.status === true) {
+        messageElement.classList.remove('alert-success');
+        messageElement.classList.add(response.statusSeverity);
+        messageElement.querySelector('.alert-heading').innerHTML = response.statusTitle;
+        messageElement.querySelector('p').innerHTML = response.statusMessage;
+        showElement(messageElement);
       }
     };
 
diff --git a/Resources/Public/JavaScript/Luxletter/Module.min.js b/Resources/Public/JavaScript/Luxletter/Module.min.js
index 4138281..b0f1601 100644
--- a/Resources/Public/JavaScript/Luxletter/Module.min.js
+++ b/Resources/Public/JavaScript/Luxletter/Module.min.js
@@ -1 +1 @@
-define(["jquery"],function(e){"use strict";function t(e){var l=this,i=!1,r=!1,t=(this.initialize=function(){t(),n(),o(),d(),s(),v(),f()},function(){for(var r=document.querySelectorAll(".wizardform > fieldset"),e=document.querySelectorAll("[data-wizardform-gotostep]"),n=document.querySelectorAll(".wizard > a"),t=1;t<r.length;t++)p(r[t]);for(var l=0;l<e.length;l++)e[l].addEventListener("click",function(e){e.preventDefault();e=this.getAttribute("data-wizardform-gotostep");a(n,"current"),n[e-1].classList.add("current");for(var t=0;t<r.length;t++)p(r[t]);h(r[e-1]),w()})}),a=function(e,t){for(var r=0;r<e.length;r++)e[r].classList.remove(t)},n=function(){u();var e=document.querySelector('select[data-luxletter-wizardpreviewevent="users"]');null!==e&&e.addEventListener("change",function(e){u()})},u=function(){var e=[],t=(void 0!==window.luxLetterReceiverChoice&&(e=window.luxLetterReceiverChoice.getValue(!0)),document.querySelectorAll('input[data-luxletter-wizardpreviewevent="users"][type="hidden"]'));if(0<t.length)for(var r=0;r<t.length;r++)e.push(t[r].getAttribute("value"));m(TYPO3.settings.ajaxUrls["/luxletter/wizardUserPreview"],{usergroups:e.join(",")},"addWizardUserPreviewCallback")},o=function(){c();var e=document.querySelector('[data-luxletter-wizardpreviewevent="newsletter"]'),e=(null!==e&&e.addEventListener("change",function(){c()}),document.querySelector('[data-luxletter-wizardpreviewevent="layout"]'));null!==e&&e.addEventListener("change",function(){c()})},c=function(){var e=document.querySelector('[data-luxletter-wizardpreview="newsletter"]'),t=document.querySelector('[data-luxletter-wizardpreviewevent="newsletter"]'),r=document.querySelector('[data-luxletter-wizardpreviewevent="layout"]');null!==e&&""!==t.value&&m(TYPO3.settings.ajaxUrls["/luxletter/previewSources"],{origin:t.value,layout:r.value},"newsletterPreviewCallback")},d=(this.newsletterPreviewCallback=function(e){var t=document.querySelector('[data-luxletter-wizardpreview="newsletter"]');t.innerHTML="";for(var r=0;r<e.length;r++){var n,l=document.createElement("div"),a=(l.setAttribute("class","luxletter-iframepreview-children"),document.createElement("iframe"));a.setAttribute("src",e[r].url),e[r].subject&&((n=document.createElement("h2")).innerHTML=e[r].subject,l.appendChild(n)),l.appendChild(a),t.appendChild(l),i=!0}},function(){var e=document.querySelector('[data-luxletter-testmail="submit"]');null!==e&&e.addEventListener("click",function(e){e.preventDefault();var e=document.querySelector('[data-luxletter-wizardpreviewevent="newsletter"]').value,t=document.querySelector('[data-luxletter-testmail="email"]').value,r=document.querySelector('[data-luxletter-testmail="subject"]'),n=document.querySelector('[data-luxletter-testmail="configuration"]').value,l=document.querySelector('[data-luxletter-wizardpreviewevent="layout"]').value;e&&t&&l&&m(TYPO3.settings.ajaxUrls["/luxletter/testMail"],{origin:e,email:t,subject:null!==r?r.value:"",configuration:n,layout:l},"testMailListenerCallback")})}),s=function(){for(var e=document.querySelectorAll("[data-luxletter-linkmockaction]"),t=0;t<e.length;t++)e[t].addEventListener("click",function(){var e=this.getAttribute("data-luxletter-linkmockaction");document.querySelector('[data-luxletter-linkmock-link="'+e+'"]').click()})},v=function(){for(var e=document.querySelectorAll("[data-luxletter-action-ajax]"),t=0;t<e.length;t++)e[t].addEventListener("click",function(e){e.preventDefault();e=this.getAttribute("data-luxletter-action-ajax");m(TYPO3.settings.ajaxUrls["/luxletter/receiverdetail"],{user:e},"userDetailListenerCallback")})},f=function(){for(var e=document.querySelectorAll("[data-luxletter-confirm]"),t=0;t<e.length;t++)e[t].addEventListener("click",function(e){var t=e.currentTarget.getAttribute("data-luxletter-confirm");!1===confirm(t)&&e.preventDefault()})},m=(this.addWizardUserPreviewCallback=function(e){var t=document.querySelector('[data-luxletter-wizardpreview="users"]');null!==t&&(t.innerHTML=e.html,r=!0,w())},this.testMailListenerCallback=function(e){var t=document.querySelector('[data-luxletter-testmail="message"]');null!==t&&!0===e.status&&(h(t),e=t.querySelector("p>span"),t=parseInt(e.innerHTML),e.innerHTML=(++t).toString())},this.userDetailListenerCallback=function(e){var t=document.getElementById("luxletter-newsletter-receiver-container");null!==t&&(t.innerHTML=e.html)},function(e,t,r){var n;void 0!==e&&""!==e?((n=new XMLHttpRequest).onreadystatechange=function(){4===this.readyState&&200===this.status&&null!==r&&l[r](JSON.parse(this.responseText))},n.open("POST",g(e,t),!0),n.send()):console.log("No ajax URI given!")}),w=function(){if(x()&&y())for(var e=document.querySelectorAll("[data-luxletter-wizardstatus]"),t=0;t<e.length;t++)"ready"===e[t].getAttribute("data-luxletter-wizardstatus")?h(e[t]):"pending"===e[t].getAttribute("data-luxletter-wizardstatus")&&p(e[t])},x=function(){return i&&r},y=function(){for(var e=document.querySelectorAll("[data-luxletter-mandatory]"),t=0;t<e.length;t++)if(0===e[t].value||""===e[t].value)return!1;return!0},g=function(e,t){for(var r in t)t.hasOwnProperty(r)&&(-1!==e.indexOf("?")?e+="&":e+="?",e+=r+"="+encodeURIComponent(t[r]));return e},p=function(e){e.style.display="none"},h=function(e){e.style.display="block"}}e(document).ready(function(){(new t).initialize()})});
\ No newline at end of file
+define(["jquery"],function(e){"use strict";function t(e){var n=this,i=!1,r=!1,t=(this.initialize=function(){t(),l(),c(),s(),d(),v(),f()},function(){for(var r=document.querySelectorAll(".wizardform > fieldset"),e=document.querySelectorAll("[data-wizardform-gotostep]"),l=document.querySelectorAll(".wizard > a"),t=1;t<r.length;t++)p(r[t]);for(var n=0;n<e.length;n++)e[n].addEventListener("click",function(e){e.preventDefault();e=this.getAttribute("data-wizardform-gotostep");a(l,"current"),l[e-1].classList.add("current");for(var t=0;t<r.length;t++)p(r[t]);h(r[e-1]),w()})}),a=function(e,t){for(var r=0;r<e.length;r++)e[r].classList.remove(t)},l=function(){u();var e=document.querySelector('select[data-luxletter-wizardpreviewevent="users"]');null!==e&&e.addEventListener("change",function(e){u()})},u=function(){var e=[],t=(void 0!==window.luxLetterReceiverChoice&&(e=window.luxLetterReceiverChoice.getValue(!0)),document.querySelectorAll('input[data-luxletter-wizardpreviewevent="users"][type="hidden"]'));if(0<t.length)for(var r=0;r<t.length;r++)e.push(t[r].getAttribute("value"));m(TYPO3.settings.ajaxUrls["/luxletter/wizardUserPreview"],{usergroups:e.join(",")},"addWizardUserPreviewCallback")},c=function(){o();var e=document.querySelector('[data-luxletter-wizardpreviewevent="newsletter"]'),e=(null!==e&&e.addEventListener("change",function(){o()}),document.querySelector('[data-luxletter-wizardpreviewevent="layout"]'));null!==e&&e.addEventListener("change",function(){o()})},o=function(){var e=document.querySelector('[data-luxletter-wizardpreview="newsletter"]'),t=document.querySelector('[data-luxletter-wizardpreviewevent="newsletter"]'),r=document.querySelector('[data-luxletter-wizardpreviewevent="layout"]');null!==e&&""!==t.value&&m(TYPO3.settings.ajaxUrls["/luxletter/previewSources"],{origin:t.value,layout:r.value},"newsletterPreviewCallback")},s=(this.newsletterPreviewCallback=function(e){var t=document.querySelector('[data-luxletter-wizardpreview="newsletter"]');t.innerHTML="";for(var r=0;r<e.length;r++){var l,n=document.createElement("div"),a=(n.setAttribute("class","luxletter-iframepreview-children"),document.createElement("iframe"));a.setAttribute("src",e[r].url),e[r].subject&&((l=document.createElement("h2")).innerHTML=e[r].subject,n.appendChild(l)),n.appendChild(a),t.appendChild(n),i=!0}},function(){var e=document.querySelector('[data-luxletter-testmail="submit"]');null!==e&&e.addEventListener("click",function(e){e.preventDefault();var e=document.querySelector('[data-luxletter-wizardpreviewevent="newsletter"]').value,t=document.querySelector('[data-luxletter-testmail="email"]').value,r=document.querySelector('[data-luxletter-testmail="subject"]'),l=document.querySelector('[data-luxletter-testmail="configuration"]').value,n=document.querySelector('[data-luxletter-wizardpreviewevent="layout"]').value;e&&t&&n&&m(TYPO3.settings.ajaxUrls["/luxletter/testMail"],{origin:e,email:t,subject:null!==r?r.value:"",configuration:l,layout:n},"testMailListenerCallback")})}),d=function(){for(var e=document.querySelectorAll("[data-luxletter-linkmockaction]"),t=0;t<e.length;t++)e[t].addEventListener("click",function(){var e=this.getAttribute("data-luxletter-linkmockaction");document.querySelector('[data-luxletter-linkmock-link="'+e+'"]').click()})},v=function(){for(var e=document.querySelectorAll("[data-luxletter-action-ajax]"),t=0;t<e.length;t++)e[t].addEventListener("click",function(e){e.preventDefault();e=this.getAttribute("data-luxletter-action-ajax");m(TYPO3.settings.ajaxUrls["/luxletter/receiverdetail"],{user:e},"userDetailListenerCallback")})},f=function(){for(var e=document.querySelectorAll("[data-luxletter-confirm]"),t=0;t<e.length;t++)e[t].addEventListener("click",function(e){var t=e.currentTarget.getAttribute("data-luxletter-confirm");!1===confirm(t)&&e.preventDefault()})},m=(this.addWizardUserPreviewCallback=function(e){var t=document.querySelector('[data-luxletter-wizardpreview="users"]');null!==t&&(t.innerHTML=e.html,r=!0,w())},this.testMailListenerCallback=function(e){var t,r,l=document.querySelector('[data-luxletter-testmail="message"]');null!==l&&void 0===e.statusSeverity&&!0===e.status?(h(l),t=l.querySelector("p>span"),r=parseInt(t.innerHTML),t.innerHTML=(++r).toString()):null!==l&&""!==e.statusSeverity&&!0===e.status&&(l.classList.remove("alert-success"),l.classList.add(e.statusSeverity),l.querySelector(".alert-heading").innerHTML=e.statusTitle,l.querySelector("p").innerHTML=e.statusMessage,h(l))},this.userDetailListenerCallback=function(e){var t=document.getElementById("luxletter-newsletter-receiver-container");null!==t&&(t.innerHTML=e.html)},function(e,t,r){var l;void 0!==e&&""!==e?((l=new XMLHttpRequest).onreadystatechange=function(){4===this.readyState&&200===this.status&&null!==r&&n[r](JSON.parse(this.responseText))},l.open("POST",x(e,t),!0),l.send()):console.log("No ajax URI given!")}),w=function(){if(y()&&g())for(var e=document.querySelectorAll("[data-luxletter-wizardstatus]"),t=0;t<e.length;t++)"ready"===e[t].getAttribute("data-luxletter-wizardstatus")?h(e[t]):"pending"===e[t].getAttribute("data-luxletter-wizardstatus")&&p(e[t])},y=function(){return i&&r},g=function(){for(var e=document.querySelectorAll("[data-luxletter-mandatory]"),t=0;t<e.length;t++)if(0===e[t].value||""===e[t].value)return!1;return!0},x=function(e,t){for(var r in t)t.hasOwnProperty(r)&&(-1!==e.indexOf("?")?e+="&":e+="?",e+=r+"="+encodeURIComponent(t[r]));return e},p=function(e){e.style.display="none"},h=function(e){e.style.display="block"}}e(document).ready(function(){(new t).initialize()})});
\ No newline at end of file