diff --git a/modules/silauth/src/Auth/Source/system/System.php b/modules/silauth/src/Auth/Source/system/System.php
index fd54055..fb8d558 100644
--- a/modules/silauth/src/Auth/Source/system/System.php
+++ b/modules/silauth/src/Auth/Source/system/System.php
@@ -4,10 +4,8 @@
 
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
-use SimpleSAML\Module\silauth\Auth\Source\auth\IdBroker;
-use SimpleSAML\Module\silauth\Auth\Source\config\ConfigManager;
+use SimpleSAML\Configuration;
 use SimpleSAML\Module\silauth\Auth\Source\models\FailedLoginIpAddress;
-use \SimpleSAML\Configuration;
 use Throwable;
 
 class System
@@ -46,7 +44,7 @@ protected function isRequiredConfigPresent(): bool
          *       HTTP_HOST value (provided by the user's request) is used to
          *       build a trusted URL (see SimpleSaml\Module::authenticate()).
          */
-        $baseURL = $globalConfig->getString('baseurlpath', '');
+        $baseURL = $globalConfig->getOptionalString('baseurlpath', '');
         $avoidsSecurityHole = (preg_match('#^https?://.*/$#D', $baseURL) === 1);
         if (!$avoidsSecurityHole) {
             $this->logError('isRequiredConfigPresent failed: baseurlpath (' . $baseURL . ') does not meet requirements');
diff --git a/modules/sildisco/public/metadata.php b/modules/sildisco/public/metadata.php
index fb03e42..45f7464 100644
--- a/modules/sildisco/public/metadata.php
+++ b/modules/sildisco/public/metadata.php
@@ -6,10 +6,9 @@
 require_once('../public/_include.php');
 
 use SAML2\Constants;
-use SimpleSAML\Utils\Auth as Auth;
+use SimpleSAML\Utils\Config\Metadata as Metadata;
 use SimpleSAML\Utils\Crypto as Crypto;
 use SimpleSAML\Utils\HTTP as HTTP;
-use SimpleSAML\Utils\Config\Metadata as Metadata;
 
 // load SimpleSAMLphp, configuration and metadata
 $config = \SimpleSAML\Configuration::getInstance();
@@ -135,7 +134,7 @@
         ));
     }
 
-    $metaArray['NameIDFormat'] = $idpmeta->getString(
+    $metaArray['NameIDFormat'] = $idpmeta->getOptionalString(
         'NameIDFormat',
         'urn:oasis:names:tc:SAML:2.0:nameid-format:transient'
     );
@@ -193,10 +192,10 @@
         }
     }
 
-    $technicalContactEmail = $config->getString('technicalcontact_email', false);
+    $technicalContactEmail = $config->getOptionalString('technicalcontact_email', false);
     if ($technicalContactEmail && $technicalContactEmail !== 'na@example.org') {
         $techcontact['emailAddress'] = $technicalContactEmail;
-        $techcontact['name'] = $config->getString('technicalcontact_name', null);
+        $techcontact['name'] = $config->getOptionalString('technicalcontact_name', null);
         $techcontact['contactType'] = 'technical';
         $metaArray['contacts'][] = Metadata::getContact($techcontact);
     }