diff --git a/apps/files_external/lib/Lib/Backend/SMB.php b/apps/files_external/lib/Lib/Backend/SMB.php
index a1fcd7fe305d9..e9bb5665606e0 100644
--- a/apps/files_external/lib/Lib/Backend/SMB.php
+++ b/apps/files_external/lib/Lib/Backend/SMB.php
@@ -55,6 +55,7 @@ public function __construct(IL10N $l, Password $legacyAuth) {
 					->setFlag(DefinitionParameter::FLAG_OPTIONAL),
 				(new DefinitionParameter('timeout', $l->t('Timeout')))
 					->setType(DefinitionParameter::VALUE_HIDDEN)
+					->setFlag(DefinitionParameter::FLAG_OPTIONAL),
 			])
 			->addAuthScheme(AuthMechanism::SCHEME_PASSWORD)
 			->addAuthScheme(AuthMechanism::SCHEME_SMB)