diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index 8f8d000..c295ce2 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -17,7 +17,9 @@
 use Drupal\Core\Database\DatabaseExceptionWrapper;
 use Drupal\Core\File\FileSystemInterface;
 use Drupal\Core\Form\FormState;
-use Drupal\Core\Installer\Exception\AlreadyInstalledException;
+use Drupal\Core\Installer\Exception\ActiveConfigurationExistsException;
+use Drupal\Core\Installer\Exception\DatabaseAlreadyPopulatedException;
+use Drupal\Core\Installer\Exception\InstallationTasksCompletedException;
 use Drupal\Core\Installer\Exception\InstallerException;
 use Drupal\Core\Installer\Exception\NoProfilesException;
 use Drupal\Core\Installer\Form\SiteSettingsForm;
@@ -514,8 +516,8 @@ function install_begin_request($class_loader, &$install_state) {
 
   if (!$install_state['database_verified']) {
     // Do not install over an existing installation. The call to
-    // install_verify_database_ready() will throw an AlreadyInstalledException
-    // if this is the case.
+    // install_verify_database_ready() will throw an
+    // DatabaseAlreadyPopulatedException if this is the case.
     install_verify_database_ready();
   }
   // Verify the last completed task in the database, if there is one.
@@ -525,7 +527,8 @@ function install_begin_request($class_loader, &$install_state) {
   if ($install_state['config_verified'] && empty($task)) {
     if (count($kernel->getConfigStorage()->listAll())) {
       $task = NULL;
-      throw new AlreadyInstalledException($container->get('string_translation'));
+      $translator = $container->get('string_translation');
+      throw new ActiveConfigurationExistsException($translator);
     }
   }
 
@@ -1127,7 +1130,8 @@ function install_verify_completed_task() {
   }
   if (isset($task)) {
     if ($task == 'done') {
-      throw new AlreadyInstalledException(\Drupal::service('string_translation'));
+      $translator = \Drupal::service('string_translation');
+      throw new InstallationTasksCompletedException($translator);
     }
     return $task;
   }
@@ -1157,7 +1161,7 @@ function install_verify_database_settings($site_path) {
 /**
  * Verify that the database is ready (no existing Drupal installation).
  *
- * @throws \Drupal\Core\Installer\Exception\AlreadyInstalledException
+ * @throws \Drupal\Core\Installer\Exception\DatabaseAlreadyPopulatedException
  *   Thrown when the database already has a table that would be created by
  *   installing the System module.
  */
@@ -1177,7 +1181,8 @@ function install_verify_database_ready() {
     }
   }
   if ($existing_install) {
-    throw new AlreadyInstalledException(\Drupal::service('string_translation'));
+    $translator = \Drupal::service('string_translation');
+    throw new DatabaseAlreadyPopulatedException($translator);
   }
 }
 
diff --git a/core/lib/Drupal/Core/Installer/Exception/ActiveConfigurationExistsException.php b/core/lib/Drupal/Core/Installer/Exception/ActiveConfigurationExistsException.php
new file mode 100644
index 0000000..e40409a
--- /dev/null
+++ b/core/lib/Drupal/Core/Installer/Exception/ActiveConfigurationExistsException.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\Core\Installer\Exception;
+
+use Drupal\Core\StringTranslation\TranslationInterface;
+
+/**
+ * Exception thrown if Drupal is installed already.
+ */
+class ActiveConfigurationExistsException extends AlreadyInstalledException {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(TranslationInterface $string_translation, $message = '') {
+    $this->stringTranslation = $string_translation;
+    parent::__construct($string_translation, $this->t('Active configuration already exists.'));
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Installer/Exception/AlreadyInstalledException.php b/core/lib/Drupal/Core/Installer/Exception/AlreadyInstalledException.php
index ca00d0b..bc9af44 100644
--- a/core/lib/Drupal/Core/Installer/Exception/AlreadyInstalledException.php
+++ b/core/lib/Drupal/Core/Installer/Exception/AlreadyInstalledException.php
@@ -7,26 +7,28 @@
 /**
  * Exception thrown if Drupal is installed already.
  */
-class AlreadyInstalledException extends InstallerException {
+abstract class AlreadyInstalledException extends InstallerException {
 
   /**
    * Constructs a new "already installed" exception.
    *
    * @param \Drupal\Core\StringTranslation\TranslationInterface $string_translation
    *   The string translation manager.
+   * @var string $specific_message
+   *   A specific message exception message.
    */
-  public function __construct(TranslationInterface $string_translation) {
-    $this->stringTranslation = $string_translation;
+  public function __construct(TranslationInterface $string_translation, $specific_message = '') {
+    $title = 'Drupal already installed.';
+
+    $message = "<ul>\n";
+    if ($specific_message !== '') {
+      $message .= '<li>' . $specific_message . '</li>';
+    }
+    $message .= '<li>To start over, you must empty your existing database and copy <em>default.settings.php</em> over <em>settings.php</em>.</li>
+<li>To upgrade an existing installation, proceed to the <a href="' . $GLOBALS['base_path'] . 'update.php">update script</a>.</li>
+<li>View your <a href="' . $GLOBALS['base_url'] . '">existing site</a>.</li>
+</ul>';
 
-    $title = $this->t('Drupal already installed');
-    $message = $this->t('<ul>
-<li>To start over, you must empty your existing database and copy <em>default.settings.php</em> over <em>settings.php</em>.</li>
-<li>To upgrade an existing installation, proceed to the <a href=":update-url">update script</a>.</li>
-<li>View your <a href=":base-url">existing site</a>.</li>
-</ul>', [
-      ':base-url' => $GLOBALS['base_url'],
-      ':update-url' => $GLOBALS['base_path'] . 'update.php',
-    ]);
     parent::__construct($message, $title);
   }
 
diff --git a/core/lib/Drupal/Core/Installer/Exception/DatabaseAlreadyPopulatedException.php b/core/lib/Drupal/Core/Installer/Exception/DatabaseAlreadyPopulatedException.php
new file mode 100644
index 0000000..5899fae
--- /dev/null
+++ b/core/lib/Drupal/Core/Installer/Exception/DatabaseAlreadyPopulatedException.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\Core\Installer\Exception;
+
+use Drupal\Core\StringTranslation\TranslationInterface;
+
+/**
+ * Exception thrown if Drupal is installed already.
+ */
+class DatabaseAlreadyPopulatedException extends AlreadyInstalledException {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(TranslationInterface $string_translation, $message = '') {
+    $this->stringTranslation = $string_translation;
+    parent::__construct($string_translation, $this->t('Database is already populated.'));
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Installer/Exception/InstallationTasksCompletedException.php b/core/lib/Drupal/Core/Installer/Exception/InstallationTasksCompletedException.php
new file mode 100644
index 0000000..60dcdb8
--- /dev/null
+++ b/core/lib/Drupal/Core/Installer/Exception/InstallationTasksCompletedException.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\Core\Installer\Exception;
+
+use Drupal\Core\StringTranslation\TranslationInterface;
+
+/**
+ * Exception thrown if Drupal is installed already.
+ */
+class InstallationTasksCompletedException extends AlreadyInstalledException {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(TranslationInterface $string_translation, $message = '') {
+    $this->stringTranslation = $string_translation;
+    parent::__construct($string_translation, $this->t('Installation tasks have already been completed.'));
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Installer/Exception/SettingsAlreadyExistsException.php b/core/lib/Drupal/Core/Installer/Exception/SettingsAlreadyExistsException.php
new file mode 100644
index 0000000..4ad6091
--- /dev/null
+++ b/core/lib/Drupal/Core/Installer/Exception/SettingsAlreadyExistsException.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\Core\Installer\Exception;
+
+use Drupal\Core\StringTranslation\TranslationInterface;
+
+/**
+ * Exception thrown if Drupal is installed already.
+ */
+class SettingsAlreadyExistsException extends AlreadyInstalledException {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(TranslationInterface $string_translation, $message = '') {
+    $this->stringTranslation = $string_translation;
+    parent::__construct($string_translation, $this->t('Configured settings.php already exists.'));
+  }
+
+}