diff --git a/htdocs/core/lib/security2.lib.php b/htdocs/core/lib/security2.lib.php
index 1cacd70d602..4b70419630f 100644
--- a/htdocs/core/lib/security2.lib.php
+++ b/htdocs/core/lib/security2.lib.php
@@ -69,8 +69,6 @@ function checkLoginPassEntity($usertotest, $passwordtotest, $entitytotest, $auth
 
 	// Validation of login/pass/entity with standard modules
 	if (empty($login)) {
-		unset($_SESSION["dol_loginmesg"]);
-
 		$test = true;
 		foreach ($authmode as $mode) {
 			if ($test && $mode && !$login) {
@@ -113,7 +111,7 @@ function checkLoginPassEntity($usertotest, $passwordtotest, $entitytotest, $auth
 					// Load translation files required by the page
 					$langs->loadLangs(array('other', 'main', 'errors'));
 
-					$_SESSION["dol_loginmesg"] = (isset($_SESSION["dol_loginmesg"]) ? $_SESSION["dol_loginmesg"].', ' : '').$langs->transnoentitiesnoconv("ErrorFailedToLoadLoginFileForMode", $mode);
+					$_SESSION["dol_loginmesg"] = (empty($_SESSION["dol_loginmesg"]) ? '' : $_SESSION["dol_loginmesg"].', ').$langs->transnoentitiesnoconv("ErrorFailedToLoadLoginFileForMode", $mode);
 				}
 			}
 		}
diff --git a/test/phpunit/SecurityTest.php b/test/phpunit/SecurityTest.php
index eabfe389174..e1180c980ef 100644
--- a/test/phpunit/SecurityTest.php
+++ b/test/phpunit/SecurityTest.php
@@ -604,7 +604,7 @@ class SecurityTest extends PHPUnit\Framework\TestCase
 
 		$login=checkLoginPassEntity('admin', 'admin', 1, array('forceuser'));
 		print __METHOD__." login=".$login."\n";
-		$this->assertEquals($login, '');    // Expected '' because should failed because login 'auto' does not exists
+		$this->assertEquals('', $login, 'Error');    // Expected '' because should failed because login 'auto' does not exists
 	}
 
 	/**