diff --git a/lib/Froxlor/Api/Commands/EmailAccounts.php b/lib/Froxlor/Api/Commands/EmailAccounts.php
index e560fd0dd4..d8799dedec 100644
--- a/lib/Froxlor/Api/Commands/EmailAccounts.php
+++ b/lib/Froxlor/Api/Commands/EmailAccounts.php
@@ -157,10 +157,10 @@ public function add()
 
 			// prefix hash-algo
 			switch (Settings::Get('system.passwordcryptfunc')) {
-				case PASSWORD_ARGON2I:
+				case defined('PASSWORD_ARGON2I') && PASSWORD_ARGON2I:
 					$cpPrefix = '{ARGON2I}';
 					break;
-				case PASSWORD_ARGON2ID:
+				case defined('PASSWORD_ARGON2ID') && PASSWORD_ARGON2ID:
 					$cpPrefix = '{ARGON2ID}';
 					break;
 				default:
@@ -404,10 +404,10 @@ public function update()
 			$password = Crypt::validatePassword($password, true);
 			// prefix hash-algo
 			switch (Settings::Get('system.passwordcryptfunc')) {
-				case PASSWORD_ARGON2I:
+				case defined('PASSWORD_ARGON2I') && PASSWORD_ARGON2I:
 					$cpPrefix = '{ARGON2I}';
 					break;
-				case PASSWORD_ARGON2ID:
+				case defined('PASSWORD_ARGON2ID') && PASSWORD_ARGON2ID:
 					$cpPrefix = '{ARGON2ID}';
 					break;
 				default:
diff --git a/tests/Emails/EmailsTest.php b/tests/Emails/EmailsTest.php
index a62b3ee005..64b812da24 100644
--- a/tests/Emails/EmailsTest.php
+++ b/tests/Emails/EmailsTest.php
@@ -426,10 +426,10 @@ public function testCustomerEmailAccountsAdd()
 		$this->assertEquals(1, $result['popaccountid']);
 
 		switch (Settings::Get('system.passwordcryptfunc')) {
-			case PASSWORD_ARGON2I:
+			case defined('PASSWORD_ARGON2I') && PASSWORD_ARGON2I:
 				$cpPrefix = '{ARGON2I}';
 				break;
-			case PASSWORD_ARGON2ID:
+			case defined('PASSWORD_ARGON2ID') && PASSWORD_ARGON2ID:
 				$cpPrefix = '{ARGON2ID}';
 				break;
 			default: