diff --git a/sources/Application/Helper/ExceptionHandlerHelper.php b/sources/Application/Helper/ExceptionHandlerHelper.php
index af83f241c..af28fa9fb 100644
--- a/sources/Application/Helper/ExceptionHandlerHelper.php
+++ b/sources/Application/Helper/ExceptionHandlerHelper.php
@@ -4,11 +4,12 @@ namespace Combodo\iTop\Application\Helper;
 
 use Combodo\iTop\Application\WebPage\ErrorPage;
 use IssueLog;
+use SimpleXMLElement;
 use Throwable;
 
 class ExceptionHandlerHelper
 {
-	static array $aSupportedMimeTypes = [
+	public static array $aSupportedMimeTypes = [
 		'application/json' => 'json',
 		'application/xml'  => 'xml',
 		'text/html'        => 'html',
@@ -17,7 +18,10 @@ class ExceptionHandlerHelper
 
 	public static function HandleException(Throwable $oException)
 	{
-		ob_end_clean();
+		$aStatus = ob_get_status();
+		if (count($aStatus) !== 0) {
+			ob_end_clean();
+		}
 
 		// Log the exception
 		IssueLog::Exception('Fatal error', $oException);
@@ -36,18 +40,23 @@ class ExceptionHandlerHelper
 		header("Content-Type: {$mime}; charset=utf-8");
 		header('Vary: Accept');
 
+		$aData = [
+			'error' => 'Fatal error',
+			'message' => 'We are sorry, an unexpected error has occurred. Please try again later.',
+
+		];
+
 		switch (self::$aSupportedMimeTypes[$mime]) {
 			case 'json':
-//				echo json_encode($data, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
+				echo json_encode($aData, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
 				break;
 
 			case 'xml':
-				// Version simple: sérialisation minimale
-//				$xml = new SimpleXMLElement('<response/>');
-//				array_walk_recursive((array)$data, function ($value, $key) use ($xml) {
-//					$xml->addChild((string)$key, htmlspecialchars((string)$value, ENT_QUOTES | ENT_XML1, 'UTF-8'));
-//				});
-//				echo $xml->asXML();
+				$oXml = new SimpleXMLElement('<response/>');
+				array_walk_recursive($aData, function ($sValue, $sKey) use ($oXml) {
+					$oXml->addChild((string)$sKey, htmlspecialchars((string)$sValue, ENT_QUOTES | ENT_XML1, 'UTF-8'));
+				});
+				echo $oXml->asXML();
 				break;
 
 			case 'html':
@@ -58,9 +67,9 @@ class ExceptionHandlerHelper
 				break;
 
 			case 'text':
-				echo 'Fatal error';
+				echo "Fatal error\n";
+				echo "We are sorry, an unexpected error has occurred. Please try again later.\n";
 				break;
-
 		}
 	}
 
@@ -88,7 +97,7 @@ class ExceptionHandlerHelper
 			$accepted[] = ['type' => $type, 'q' => $q];
 		}
 
-		usort($accepted, fn($a, $b) => $b['q'] <=> $a['q']);
+		usort($accepted, fn ($a, $b) => $b['q'] <=> $a['q']);
 
 		foreach ($accepted as $a) {
 			foreach ($supportedMimes as $mime) {
@@ -107,4 +116,4 @@ class ExceptionHandlerHelper
 
 		return null;
 	}
-}
\ No newline at end of file
+}
diff --git a/sources/Application/TwigBase/Controller/Controller.php b/sources/Application/TwigBase/Controller/Controller.php
index d60e6e518..ee3689f3c 100644
--- a/sources/Application/TwigBase/Controller/Controller.php
+++ b/sources/Application/TwigBase/Controller/Controller.php
@@ -23,7 +23,6 @@ namespace Combodo\iTop\Application\TwigBase\Controller;
 use ApplicationMenu;
 use Combodo\iTop\Application\TwigBase\Twig\TwigHelper;
 use Combodo\iTop\Application\WebPage\AjaxPage;
-use Combodo\iTop\Application\WebPage\ErrorPage;
 use Combodo\iTop\Application\WebPage\iTopWebPage;
 use Combodo\iTop\Application\WebPage\WebPage;
 use Combodo\iTop\Controller\AbstractController;
@@ -261,29 +260,29 @@ abstract class Controller extends AbstractController
 	 */
 	public function HandleOperation(): void
 	{
-		try {
-			$this->CheckAccess();
-			$this->m_sOperation = utils::ReadParam('operation', $this->sDefaultOperation);
+		//		try {
+		$this->CheckAccess();
+		$this->m_sOperation = utils::ReadParam('operation', $this->sDefaultOperation);
 
-			if ($this->CallOperation(utils::ToCamelCase($this->m_sOperation))) {
-				return;
-			}
-
-			// Fallback to unchanged names for compatibility
-			if ($this->CallOperation($this->m_sOperation)) {
-				return;
-			}
-
-			$this->DisplayBadRequest();
-		} catch (Exception $e) {
-			http_response_code(500);
-			$oP = new ErrorPage(Dict::S('UI:PageTitle:FatalError'));
-			$oP->add("<h1>".Dict::S('UI:FatalErrorMessage')."</h1>\n");
-			$oP->add(get_class($e).' : '.utils::EscapeHtml($e->GetMessage()));
-			$oP->output();
-
-			IssueLog::Exception('HandleOperation failed for '.json_encode($this->m_sOperation), $e);
+		if ($this->CallOperation(utils::ToCamelCase($this->m_sOperation))) {
+			return;
 		}
+
+		// Fallback to unchanged names for compatibility
+		if ($this->CallOperation($this->m_sOperation)) {
+			return;
+		}
+
+		$this->DisplayBadRequest();
+		//		} catch (Exception $e) {
+		//			http_response_code(500);
+		//			$oP = new ErrorPage(Dict::S('UI:PageTitle:FatalError'));
+		//			$oP->add("<h1>".Dict::S('UI:FatalErrorMessage')."</h1>\n");
+		//			$oP->add(get_class($e).' : '.utils::EscapeHtml($e->GetMessage()));
+		//			$oP->output();
+		//
+		//			IssueLog::Exception('HandleOperation failed for '.json_encode($this->m_sOperation), $e);
+		//		}
 	}
 
 	/**