diff --git a/setup/wizardsteps/WizStepModulesChoice.php b/setup/wizardsteps/WizStepModulesChoice.php
index 802f0f6f9..b7bb07884 100644
--- a/setup/wizardsteps/WizStepModulesChoice.php
+++ b/setup/wizardsteps/WizStepModulesChoice.php
@@ -478,6 +478,7 @@ EOF
 	 * @param string $sParentId Used for recursion
 	 *
 	 * @return string A text representation of what will be installed
+	 * @throws \Exception
 	 */
 	public function GetSelectedModules($aInfo, $aSelectedChoices, &$aModules, $sParentId = '', $sDisplayChoices = '', &$aSelectedExtensions = null)
 	{
@@ -507,8 +508,8 @@ EOF
 				(isset($aSelectedChoices[$sChoiceId]) && ($aSelectedChoices[$sChoiceId] == $sChoiceId))) {
 				$sDisplayChoices .= '<li>'.$aChoice['title'].'</li>';
 				if (isset($aChoice['modules'])) {
-					if (count($aChoice['modules']) === 0) {
-						//throw new Exception('Extension '.$aChoice['extension_code'].' does not have any module associated');
+					if (count($aChoice['modules']) === 0 && (!isset($aChoice['missing']) || $aChoice['missing'] === false)) {
+						throw new Exception('Extension '.$aChoice['extension_code'].' does not have any module associated');
 					}
 					foreach ($aChoice['modules'] as $sModuleId) {
 						$bSelected = true;
diff --git a/tests/php-unit-tests/unitary-tests/setup/WizStepModulesChoiceTest.php b/tests/php-unit-tests/unitary-tests/setup/WizStepModulesChoiceTest.php
index 322878690..04429c87d 100644
--- a/tests/php-unit-tests/unitary-tests/setup/WizStepModulesChoiceTest.php
+++ b/tests/php-unit-tests/unitary-tests/setup/WizStepModulesChoiceTest.php
@@ -2,15 +2,13 @@
 
 namespace Combodo\iTop\Test\UnitTest\Integration;
 
-use Combodo\iTop\Application\WebPage\WebPage;
 use Combodo\iTop\Test\UnitTest\ItopTestCase;
-use iTopExtension;
 use iTopExtensionsMap;
 use iTopExtensionsMapFake;
 use ModuleDiscovery;
+use WepPageFake;
 use WizardController;
 use WizStepModulesChoiceFake;
-use WepPageFake;
 use XMLParameters;
 
 class WizStepModulesChoiceTest extends ItopTestCase
@@ -930,6 +928,40 @@ class WizStepModulesChoiceTest extends ItopTestCase
 		$this->oStep->GetSelectedModules($aStepInfo, ['_0' => '_0'], $aModules, '', '', $aExtensions);
 	}
 
+	public function testGetSelectedModulesShouldNotThrowAnExceptionWhenAMandatoryModuleIsMissing()
+	{
+		$aExtensionsMapData = [];
+		$this->oStep->setExtensionMap(iTopExtensionsMapFake::createFromArray($aExtensionsMapData));
+
+		//GetSelectedModules
+		$aStepInfo = [
+			'title' => 'Extensions',
+			'description' => '',
+			'banner' => '',
+			'options' => [
+				[
+					'extension_code' => 'combodo-sample',
+					'title' => 'Sample extension',
+					'description' => '',
+					'more_info' => '',
+					'default' => true,
+					'modules' => [],
+					'mandatory' => true,
+					'source_label' => '',
+					'uninstallable' => true,
+					'missing' => true,
+				],
+			],
+		];
+
+		$aModules = [];
+		$aExtensions = [];
+		$this->oStep->GetSelectedModules($aStepInfo, ['_0' => '_0'], $aModules, '', '', $aExtensions);
+		$this->assertCount(0, $aModules);
+		$this->assertCount(1, $aExtensions);
+
+	}
+
 	public function ProviderDisplayOptions()
 	{
 		return [